Nos3#464 eps checkout

[kevincbruce]

Added a checkout application for the generic_eps component. Have verified the checkout launches and can be commanded in the newest push. The branch is set up so that the top level files should be set up as normal in dev, and thus need to be modified to work the checkout. The old checkout was based off our old sample format before we changed our file structure from support to standalone, and had a few other errors (passing addresses instead of values and vice versa, no nos_link, expecting 1 and 3 tokens opposed to 0 and 2 for hk and switch (respectively), etc) which have been amended. It should also take hex inputs for values by using strtol, so that it matches its help.

The only concern I still see:

• The sim is slow to connect to 42. Wait, and it eventually will, after spamming out port listening messages for a while. I am not sure why it is so slow to connect. May be worth further investigation. At least now it works eventually, after the fixes to the configuration.py done earlier today for CSS. May be another thing in configure, or something else. But I'm not seeing anything obvious.

Steps:

Enable EPS in the NOS3 minimal config, switch to using the minimal config in the top level no3 mission config, and uncomment the Electrical Power System (EPS) part of checkout.sh in scripts.

make clean
make debug
cd components/generic_css/fsw/standalone/build
(mkdir build in the standalone directory if needed, then cd build)
make clean (if build directory already exists)
cmake .. -DTGTNAME=cpu1
make
exit
make clean
make
make checkout

The following submodule PRs must be merged and updated first:

nasa-itc/generic_eps#11

Closes #464