Implement is_superselector sass function

[mgreter]

Based on #1064

This is mainly for me to try out is superselector behavior which is one root problem of our selector deduping issues (which covers pretty much all of the currently still open confirmed bug issues).
It may also be a base to get the work done by @onedayitwillmake merged into master for 3.3.

[mgreter]

By sheer accident I seem to have fixed #823, #1063 and #1091 😀
Plus we pass a lot more of the is_superselector spec tests added in #963

IMO we should be able to include the improvements for 3.2.4, since they are clear bugfixes.
@xzyfer would you want to hold off the is_superselector function for 3.3!? I would ship it.

[xzyfer]

If you think it's ready we can ship it now. I'm keen to tag 3.2.4 in the
next hour or so.
On 13 May 2015 09:28, "Coveralls" notifications@github.com wrote:

[image: Coverage Status] https://coveralls.io/builds/2548983

Coverage decreased (-0.15%) to 79.97% when pulling ea659cd
ea659cd
on mgreter:feature/selector-functions-basic into 28ee088
28ee088
on sass:master.

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#1202 (comment).

[mgreter]

OK, just a few moments ... let me clean up some white-space and comments ...

[mgreter]

Also let's wait for CI here, then activate all spec tests and re-start the CI to check again ...

[coveralls]

Coverage decreased (-0.01%) to 80.11% when pulling ff3f8a0 on mgreter:feature/selector-functions-basic into 28ee088 on sass:master.

[xzyfer]

Great. I think there are some specs that need to be activated from the
recent PRs as well.
On 13 May 2015 09:39, "Coveralls" notifications@github.com wrote:

[image: Coverage Status] https://coveralls.io/builds/2549041

Coverage decreased (-2.53%) to 77.59% when pulling ff3f8a0
ff3f8a0
on mgreter:feature/selector-functions-basic into 28ee088
28ee088
on sass:master.

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#1202 (comment).

[coveralls]

Coverage increased (+0.13%) to 80.25% when pulling f8074a0 on mgreter:feature/selector-functions-basic into 28ee088 on sass:master.

[mgreter]

As always, I just create a big activate patch for the next release.
sass/sass-spec#379

[mgreter]

Merged spec activation patch and restarting CI rebuild now ...