* src/misc/intvcmp2.cc (stream_compression_base::run): Fix a case
where the "id" of the compression to use would be miscalculated,
causing wrong values to be encoded.
* src/tgbatest/intvcmp2.cc: Add this particular test case.
* src/misc/intvcmp2.cc (stream_compression_base::run):
Implement a shift-less encoding for the 1-bit and 3-bit cases.
Also declare offsets as size_t, to help 64-bit compilers.
* src/misc/intvcmp2.cc (int_array_array_compression): Specify full
type of stream_compression_base<int_array_array_compression> in
constructor to please g++ versions <= 4.3.