Fix array bounds crash in -processAvailabilityBlockInString

Fixes #349 and failing test case:
```
GBCommentsProcessorRegistrationsTesting
testProcessCommentWithContextStore_combinations_shouldRegisterMethodDescriptionBlock
```
docsetFeedFormats is not a string

Remove support for templates in `--docset-feed-formats` option, which is not necessary and does not work. Write a proper test case that does not crash. Fix compiler warnings on conversion of enum to id.
Fix crash when setting --xcrun-path or --docset-xml-filename

These items aren't properly capitalized by DDGetoptLongParser and result in a KVC exception.

This is a somewhat dirty way to handle this, but the other option I see is to rename the instance variables to use DDGetoptLongParser's capitalization, which doesn't seem better.
Apply recommended warnings for Xcode 4.6
Fix placeholder replacement test case
Merge pull request #361 from paulmelnikow/fix_tests

Fix failing test cases