Tests: add new unit tests for SlaveStatus

A few more tests in order to test Buildslave.status ... yes it's going away, but doenst hurt to have tests :)
Slave: add 'info' dictionary

Make the 'info' dictionary more public and provide hooks to update it and set it
SetSlaveInfo step to correspond to SetProperties
Interpolate("%(slave:XXXX)s")
SlaveInfo: doc in progress
Fix Travis issue: duplicate function.

The other function seemed bogus and I think was a relic.
SlaveInfo: fix pep8 issues
Fix split files with spaces
Decode comment and file path
Tests now check file path with spaces and octal encoded
Rename MsBuild to MsBuild4 to specify version number

Also add MsBuild alias for backward compatibility
Simplify MsBuild12 by factoring out path to vcvarsall.bat
Merge branch 'SlaveInfo' of git://github.com/jaredgrubb/buildbot

+autopep8
Make GitPoller break filenames on newlines

List of changed files was incorrectly splitting on spaces, instead of
just newlines. That was breaking a single file's path into multiple
lines instead of displaying it one just one.
fixed_gitpoller_changes_with_space.patch
Merge branch 'bug2529'

+autopep8
Merge branch 'git_improvements' of git://github.com/Ratio2/buildbot

+autopep8
Merge branch 'master' of git://github.com/shoelzer/buildbot