Release 0.20.1-incubating-rc2

e6134da Make cppckecker independ of pcre (#3224)
71b1c6e Add license headers to ubuntu18 docker files and add cloudpickle to rat exception file (#3218)
9c1cc16 Add an index column in all topologies page (#3216)
ea03ca1 Support overriden configuration in ckpmanager (#3215)
9d24c94 Enable gperftool HEAPCHECK in integration test (#3201)
7e249ef Update build-docker.sh (#3197)
5023515 Add favicon (#3206)
5d06b1b adapt the Bazel output directory for the incubator-heron project name (#3214)
2bfe579 EventLoop Signal Handler (#3212)
0f2a898 Added logging an error status code when stream manager can not connect to tmaster (#3208)
fde712f Update WORKSPACE info for zookeeper http archive. (#3205)
5269251 fixtypo (#3203)
0369acc Boost default maxNumInstancesPerContainer (#3200)
7ea8b8c Refactor FirstFitDecreasingPacking to support CPU intensive topologies (#3195)
bf1a710 Fix a path in scripts/ci/build_maven_artifacts.sh (#3199)
f1e6544 Add a spouts directory and README for spout implementations (#3169)
138cddc Add cppchecker static check (#3194)
251098b Change tmaster/stmgr uptime granularity to be 1 second (#3190)
dc4c733 Consolidate Packing (#3187)
2e498cb Make 0 stat visible in Heron UI (#3192)
e56eca0 Remove 'Kubernetes' in SPI function name (#3193)
c066c76 init (#3191)
fe39a46 Revamp Packing tests (#3188)
22a57f5 Modularize packing-related constraints and exceptions (#3186)
b3a215e Add packing related configs (#3185)
dd76557 Update pom template for Heron artifacts (#3182)
9b846ec Add ci script for building docker image (#3181)
8a6949b [Streamlet] Fix streamlet config to apply cpu and ram in topology (#3180)
3ebfff7 Soften padding constraint (#3178)
d83a0be Add log line to avoid ambiguity (#3177)
e82293b Add build scripts for ci jobs (#3174)
d5e2bc3 Another memory leak in stmgr-client (#3176)
d6afa82 Fix memory leak in stmgr when measuring tuple data size (#3175)
2cbd858 Add simulator maven pom file (#3171)
eb7ab2c Add target to generate packages for heron simulator (#3163)
dd6b3d4 Joshfischer/aws helm fix (#3168)
d5e809b fix all example topologies (#3167)
8ac36a2 create a symbolic link for kubernetes conf after loading docker image (#3161)
00903d1 remove heron-core.tar.gz from docker image (#3164)
37d5dc2 keep executor running when heron update adds containers (#3162)
1c0f161 Support instance healthcheck api (#3157)
9e2afd0 Yaoli/fix dockerfiles (#3160)
297eb24 Fix docker build artifacts script to have the correct version string (#3156)
1b00029 Add tooltip for component connections (#3155)
94de4fa Fix RoundRobinPacking repack with no specified numContainers (#3152)
013bf35 Clean up metrics section in Heron UI (#3153)
a1b761f Validate resource constraint (RAM and CPU) in RoundRobinPacking (#3142)
5270725 Update topology UI to make topology info more consistent across pages (#3151)
9299db9 Add a release-yaml-file argument to CLI (#3150)
3fcf94d Clean up a url format code (#3149)
c6a7e66 Document new streamlet operations in Heron website (#3148)
16e254c [UI] Move reset view button to left and change plan graph listener from click to dblclick (#3147)
d21bcb4 remove .sh files from docker image (#3146)
0ec33b9 Refactor KVStreamlet to make it lighter and easier to convert from Streamlet (#3135)
3ca8bfb Update backpressure explanation in Heron architecture doc (#3145)
23f3ff2 Add a new streamlet integration test with keyBy, countByKey and … (#3140)
ed0cff8 Clean up heron-client-install.sh (#3141)
d0141cb Add simulator into release package, and explicitly add java/scala api (#3144)
65b5e6c Fix integration test script on mac (#3143)
972687d Nwang/add byte received metric (#3136)
1327dc1 Update integration test runner to support language and test selection (#3139)
67f0d7a typo (#3138)
b42f5dc Refactor StreamletShadow class to be more general (#3134)
738ba82 Add sum/min/max reducers (#3132)
74b85d7 Nwang/add count and reduce operations in streamlet (#3131)
103bfc1 Add KVStreamlet and keyBy() operation (#3125)
93d6c38 ByteAmount String Format (#3129)
b869041 Fix docker rc and scripts for building heron (#3130)
8cef739 Nwang/fix streamwindowoperator generic types (#3124)
5c42171 Add CumulativeCountMetric and metrics to monitor instance task and metrics collection (#3127)
015be50 Add favicon (#3128)
6d56a09 Refactor window operations to avoid WindowConfigImpl cast (#3123)
a201965 Add util function for registerTopologyTimerEvents in Config (#3126)
4d1ab84 [Scala Streamlet API] Add Integration Test for Source and Union Operations (#3121)
099f5a0 Add withStream() in Streamlet to support stream selection (#3109)
3619588 [Java Streamlet API] Support Abstractions on Streamlet Sources (#3118)
de2b3d7 Support utils.Time of kafka-client-spout (#3116)
38060b0 Nwang/add streamlet operator interfaces with grouping v2 (#3099)
97ee690 [Java Streamlet API] Move Source Logics to Builder (#3115)
0f5d0d8 Enable Streamlet Scala API Documentation (#3114)
8f44c11 [Java Streamlet API] Support abstractions on Streamlet Operators (#3112)
cbf7e51 Update mailing list informtion in contributing.md (#3110)
a81021a [Java Streamlet API] Extend Validations Part II (#3111)
57b308c Nwang/add spout based source streamlet (#3032)
67b26cf fix typo (#3108)
ff53016 Port Scala Streamlet integration tests to Java (#3105)
67af633 [Java Streamlet API] Extend validations (#3095)
cbe1e42 Fix build error on Mac. (#3102)
1b05035 Add support for building Heron release in a Ubuntu 18.04 docker container (#3097)
34a64f6 Nwang/refactor custom operator interface v2 (#3100)
d40b60f Fix number of tasks in Streamlet RemapCustomGrouping (#3098)
c2e9754 Update pidhandler.py (#3094)
8218195 enablebool (#3056)
e292f02 Add interfaces IStreamletOperator, IStreamletBasicOperator and IStrea… (#3051)
7435f1d Update S3 uploader documentations (#3053)
50de70b add back stmgr metrics (#3052)
72293cf Nwang/refactor grouping (#3040)