Improved unit tests to test for the fact that reclaim should
reset the tape occupancy field.

The following unit now "succesfully" fails:

[ RUN      ] InMemory/cta_catalogue_CatalogueTest.reclaimTape_full_lastFSeq_1_no_tape_files/0
/home/smurray/CTA/catalogue/CatalogueTest.cpp:7029: Failure
Value of: tape.dataOnTapeInBytes
  Actual: 1
Expected: 0
[  FAILED  ] InMemory/cta_catalogue_CatalogueTest.reclaimTape_full_lastFSeq_1_no_tape_files/0, where GetParam() = 0x7fc58e93eab0 (7 ms)

The next step is to fix the bug in reclaim.