Adding SQLite implementation for AssetMetadataMapping
forgot to pull before pushing
Merge branch 'unit_test' of https://github.com/johnmangan/cards into unit_test
Added SQLLite AssetMetadataMapping to CMakelists
Fixed some small bugs in the SQL file
Fixed AssetMetadataMappingSQLLiteDatabase bugs, ready for testing
Pair programmed with Cameron H.

Added unit test for metadatamapping
Merge branch 'unit_test' of https://github.com/johnmangan/cards into unit_test
* Fixed some errors in RankedSearchImpl and added a default parameter to the interface.
* Added a RankedSearch test suite.
* Cleaned up part of the test application. (memory leaks)
Merge branch 'unit_test' of https://github.com/johnmangan/cards into unit_test

* Removed SQLLite implementation of AssetMetadataMapping module from the CMakeLists.txt so that we can build.

Conflicts:
	test/tests.cpp
Merge branch 'unit_test' of https://github.com/johnmangan/cards into unit_test
* Updated CMakeLists.txt since unit test headers need not be included.
* Adding the missing MetadataTagComparator to the MetaAssetSetMap typedef in AssetMetadataMappingMemoryImpl header.
* Added a default ctor to the QueryInterface implementation, allowing black-box conceptualizing that ignores internal modules (like the AccessManager).
* Modified the QueryInterface implementation to remove the need for AssetLocator modules to have defensive programming within the getFilepath function. (Removed the coupling, leaving the defensive check in the AssetLocator implementation incase an untracked AssetTag is passed in.)
* Fixed a huge bug - unintended AssetTag deletion.
* Added the QueryInterface test suite.
* Split many of the tests up into individual unit tests and integration tests (which test all combinations of available module implementations).
Merge branch 'unit_test' of https://github.com/johnmangan/cards into unit_test
* Uncommented the lines of the SQLite DB implementation of AssetMetadataMapping module in the CMakeLists.txt, since Sid has fixed it so that it compiles.
* Including the SQL DB implementation in the test application, but left the addition of the test as a comment line (see the diff to see where), since it isn't currently passing tests.
update for test
Updated to only create tables if they don't exist