Change suffix pattern to avoid matching things like "participants" in "participants.tsv" #380
Description
didn't check what would happen if I add a suffix column to participants.tsv but imho smells like a regression which caused suffix to be added where it shouldn't be... please confirm or clarify:
$> python -c 'import bids as b; print(b.__version__); print(b.BIDSLayout(".").get_collections(level="dataset")[0].to_df().to_dict(orient="records"))'
0.7.0
[{'language': '\xd1\x80\xd1\x83\xd1\x81\xd1\x81\xd0\xba\xd0\xb8\xd0\xb9', 'gender': nan, 'age': '30-35', 'handedness': 'r', 'hearing_problems_current': 'n', 'subject': '01'}, {'language': 'english', 'gender': 'f', 'age': '20-25', 'handedness': 'r', 'hearing_problems_current': 'n', 'subject': '03'}]now with 0.7.1 -- see "suffix" to appear:
$> python -c 'import bids as b; print(b.__version__); print(b.BIDSLayout(".").get_collections(level="dataset")[0].to_df().to_dict(orient="records"))'
0.7.1
[{u'suffix': 'participants', 'language': '\xd1\x80\xd1\x83\xd1\x81\xd1\x81\xd0\xba\xd0\xb8\xd0\xb9', 'gender': nan, 'age': '30-35', 'handedness': 'r', 'hearing_problems_current': 'n', 'subject': '01'}, {u'suffix': 'participants', 'language': 'english', 'gender': 'f', 'age': '20-25', 'handedness': 'r', 'hearing_problems_current': 'n', 'subject': '03'}]
```shell
$> cat participants.tsv
participant_id gender age handedness hearing_problems_current language
sub-01 n/a 30-35 r n русский
sub-03 f 20-25 r n english