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
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
Merge pull request #303 from enewton/master

Fix for issue #242 "xunit dies on undefined steps" WITH TESTS!
unicode characters in the step names do not cause xunit plugin to break
unicode characters in the step names do not cause xunit plugin to break
Translating an untranslated Norwegian string
Merge pull request #306 from JensRantil/minor-norwegian-translation

Translating an untranslated Norwegian string
Swedish language strings

They were partially based on the Norwegian translation. Norwegian
(Bokmål) is very similar to Swedish.
Translating an untranslated Norwegian string
Merge branch 'JensRantil-swedish-language'
trying to utf-8 encode all possible unicode strings
xunit plugin does not throw exception when missing step definition
Print step that failed in verbosity=2
Extract a Reporter class for use in plugins