Improved support for BLOBs

Added the support for very large objects (4TB) when backend is at least 9.3 using lo_xxx64 functions (see [release 9.3 notes](http://www.postgresql.org/docs/9.3/static/release-9-3.html#AEN115624)).

Added support for various JDBC4 methods related to Blobs: 
- setBlob with input stream in PreparedStatement
- getBinaryStream with position and offset in Blob (also helps a lot handling very large objects)

BTW, changed junit dependency to 4.11 to get assertArrayEquals