parses out '@' from CLI and test for cascading tag

CLI now accepts @ for the tag argument without failing.  This was more
because I'm lazy and didn't want to update all our CI runners that I had
set up for my pull request, but also because I think it's nice to have
the option of doing both.  Many people I've talked to consider the tag
to include the '@'

I also added a very basic test that covers the cascading of tags from
feature to their child scenarios.  Hope it's helpful, and I really hope
I have the chance to get back to submitting on it

[272]
Adds tag parsing to features

Add tag parsing logic from scenarios up to the feature as well.  Also
extends a unit test to cover a scenario that we ran into where tags
would break when the previous scenario ended with a table.

[272]
Fixes issue where no tag was passed in CLI
Merge branch 'gabrielfalcao'
parses out '@' from CLI and test for cascading tag

CLI now accepts @ for the tag argument without failing.  This was more
because I'm lazy and didn't want to update all our CI runners that I had
set up for my pull request, but also because I think it's nice to have
the option of doing both.  Many people I've talked to consider the tag
to include the '@'

I also added a very basic test that covers the cascading of tags from
feature to their child scenarios.  Hope it's helpful, and I really hope
I have the chance to get back to submitting on it

[272]
Adds tag parsing to features

Add tag parsing logic from scenarios up to the feature as well.  Also
extends a unit test to cover a scenario that we ran into where tags
would break when the previous scenario ended with a table.

[272]
Fixes issue where no tag was passed in CLI
Fixed merge error in unit tests
Merge in changes from gabrielfalcao/master

Conflicts:
	tests/unit/test_feature_parser.py
starting to implement background
first step on parsing backgrounds appropriately
basic background functionality
parsing backgrounds without MMF
refactoring background parsing
implementing basic output of backgrounds
re-enabling 2 commented tests
implementing the colored output of backgrounds
releasing 0.2.10, support to backgrounds, closes #269
fixing tests
Merge remote-tracking branch 'gabrielfalcao/master'