DRILL-2031: Parquet bit column reader fix
Removes attempted optimized bit reader, left a comment where it was removed as a pointer back to this change set. For now the higher level Parquet interface will be used to ensure reading is correct, a fix of the optimized reader can be pursued at a later date if is is necessary.
Fixed two bugs in the test framework necessary to verify the fix against the complex parquet reader (which uses a similar interface, but it ensures that none of the other columns are read incorrectly).
Fix conflict between parquet bit reader fix and vector reallocation changes.
