Cut over StringScriptDataComparator to use BytesRef instead of Strings

Closes #2920
Fall back to local statistics if global statistics are not availalbe for a field or term

Closes #2926
If searchContext not set, abort parsing and throw ISE
Upgrade to lucene 4.3
RC
Enable Geo-Shape Relations Within and Disjoint
Added test that fails pre Lucene 4.3 due to highlighter bugs

Closes #2931