Print warning if we're unable to find/parse config

See travis-ci/travis-ci#814, and probably many more issues.

This is a very simple initial implementation for handling this problem.
We may want to actually put the parse error in the payload at some point
and print that, or maybe validate the .travis.yml file somehow, but this
works as a beginning.
Merge pull request #70 from travis-ci/hh-warn-on-parse-error

Print warning if we're unable to find/parse config
Add newlines to end of .travis.yml parse warnings
Color part of .travis.yml parse warnings yellow
Error a build if we couldn't parse the YAML file

Fixes travis-ci/travis-ci#814.

While there is an argument that no .travis.yml file should make the
build run using default settings for legacy reasons, if a user does
provide a .travis.yml file and it's not valid YAML then I can't think of
a reason why the user still would want the build to be run.
Merge pull request #71 from travis-ci/hh-error-build-on-parse-error

Error a build if we couldn't parse the YAML file
Mark the job as started before we mark it as finished

In the words of the grrrreat and powerful Josh:
> Looks ugly and good, ship it.

This *really* should be handled in Gatekeeper or Hub and never even hit
the worker...
update all the deps, mostly for build and support changes
Update travis-build

- Update RubyMotion detection to detect 2.0 projects
- Announce CocoaPods and RubyMotion versions
- Copy Go repositories to the $GOPATH and run tests from there
- Remove --quiet from mvn install
- Add retries to install scripts
Update travis-build
Update travis-build

- Change Firefox addon to use http instead of ftp