* Clean up minor warnings from LGTM.com
LGTM (Semmie) is a tool, bought by GitHub last year, that conducts basic
linting tasks on code and HTML.
Clean up the warnings identified in the latest report:
https://lgtm.com/projects/g/esp8266/Arduino/?mode=list
No functionality should change, however this may fix some issues with
the perl utilities not exiting properly on a Ctrl-C from the command
line.
* Back out HTML changes and rerun boards.txt.py
Convert the continuous integration process to use GitHub's internal
CI cloud. Allows us to run up to 20 jobs in parallel, speeding up
CI immensely. Keep a short Travis-CI run, too, just for sanity and backup.
Uses new keys and secret when publishing a release to
esp8266.github.io.
