Switch to docker based build for Travis

1. Won't time out
2. More reproducible
3. If @cgreene does it, it must be good

.travis.yml

@@ -1,13 +1,11 @@
-language: r
-cache: packages
-sudo: false
-warnings_are_errors: false
+language: bash
+sudo: required
 
-install:
-  - Rscript install-packages.R
-
-script:
-  - Rscript PortalForecasts.R
+before_install:
+  - docker pull weecology/portal_predictions
+  - docker run --name ppred -t -d weecology/portal_predictions /bin/bash
 
-after_success:
-  - bash update_repo.sh
+script:
+  - docker exec -i ppred git clone https://github.com/weecology/portalPredictions.git
+  - docker exec -i ppred bash -c "cd portalPredictions && Rscript PortalForecasts.R"
+  - docker exec -i ppred bash -c "cd portalPredictions && bash update_repo.sh"

Dockerfile

@@ -0,0 +1,12 @@
+# Use an official Python runtime as a parent image
+FROM rocker/tidyverse:latest
+
+# Install `curl` since apparently it isn't in the Rocker images
+
+RUN apt-get update && apt-get install -y curl
+
+# Copy the install script
+ADD install-packages.R .
+
+# Install any needed packages specified in requirements.txt
+RUN Rscript install-packages.R