Fix 'No previous prototype for function' compiler warning

for YDBExtractFileNameWithoutExtension() function in
YapDatabaseLogging.m
Merge pull request #25 from wisenomad/master

Fix 'No previous prototype for function' compiler warning
Merge branch '2.3'
Update README.md
Update README.md
Bug fix: Forgot to finalize some sqlite statements. Might have resulted in the following error message: “Error in sqlite_close: 5 unable to close due to unfinalised statements”
Update README.md
Bug fix for method nearestIndexPathForRow when using consolidated grouping
Bug fix for issue #27 - groupingBlock & sortingBlock were not being set properly in all scenarios
Update README.md
Minor optimization - adding early bailout if given key is nil
Bug fix for non-persistent views. Fixes case where re-registering a non-persistent view immediately upon app launch may result in an empty view.
Merge branch 'master' of https://github.com/yaptv/YapDatabase
Adding podspec
Fixing podspec
Adding several more convenience methods to simplify fetching objects with a view + mappings.
Skipping an unnecessary array copy.
Minor documentation improvements
Merge branch 'master' into 2.4

Resolved Conflicts:
	YapDatabase/YapDatabaseConnection.m
Adding unit tests for automatic unregistration of extension dependencies