fold services
remove bogus module
remove nonsense timings (e.g. on `[runtime] --version`)
clean up some sh.cmd options
re-prettify a few things
do not hide user provided TRAVIS_* env vars
always export TRAVIS_LANGUAGE
simplify env vars, use Ruby tainting for secure env vars
push replacing secure env var display value down to the generator
shellescape all builtin env var values
raise an exception if tainted output ends up in the compiled code
improve spec coverage for Env
Display system_info output if it exists
Change anticipated text file location

After looking at http://www.wikiwand.com/en/Filesystem_Hierarchy_Standard
and some discussion about Homebrew unlikely to be happy with
`/usr/local` being used, we settle with
`/usr/share/travis/sytem_info` as a better location going forward.
Merge pull request #328 from travis-ci/sf-prettify

Cleanup after sf-sexp-2 diff cleaning
Merge pull request #330 from travis-ci/sf-taint-env-vars

Taint env vars
do not assert bundle clean
Merge pull request #331 from travis-ci/sf-dont-assert-bundle-clean

Do not assert bundle clean
reduce the number of git folds
make Git a higher level class, strategies Tarball, Clone, SshKey