Modified check_id_map.py to by default not strip leading/trailing whitespace and quote characters. Other script calls to map parsing function should still strip these. Modified test_check_id_map.py to test this case of mapping file format. Added some details to doc/documentation/file_formats.rst to reflect some of the stripping to be expected in mapping files.
Modified documentation/file_formats.rst to reflect quote character/whitespace stripping
Modified documentation/file_formats.rst to reflect quote character/whitespace stripping
Merge pull request #1138 from walterst/check_id_map_sampleid_whitespace

Modified check_id_map.py to by default not strip leading/trailing whites...