Parsing metadata information directly from git repo (in the absence of checkout files)

[czechboy0]

• added as the last resort when neither xccheckout nor xcscmblueprint file is found
• parses information directly from the repo
• caveat: bots created from this metadata cannot be edited without going corrupt (because I can't reproduce the same workspace hash identifier as Xcode and when you try to edit it, it gets corrupt on saving)

Fixes #186.

[buildasaur]

Result of Integration 1

Duration: 1 hour, 32 minutes and 57 seconds
Result: -1 error, failing state: internal-build-error

[buildasaur]

Result of Integration 2

Duration: 4 minutes and 38 seconds
Result: All 33 tests passed, but please fix 2 warnings.
Test Coverage: 23%.

[czechboy0]

This still uses checkout files when available, because then we get the correct workspace identifier (and bots created this way can be edited from Xcode). This just adds a fallback option for repos that don't have a checkout/blueprint file, so that they can still use Buildasaur.

It would be a nice improvement to find out how Xcode generates the workspace identifier, so that we can do the same and have all our bots easily editable from Xcode.