ASTextKit CoreText attributes cleanse bug

[bsmith11]

Fixed ASTextKit CoreText attributes bug which was incorrectly reading an NSParagraphStyle as CTParagraphStyleRef

[bsmith11]

#940

[appleguy]

Space after // - also should go ahead and link to this issue or give slightly more description on the expected behavior, as it currently is unclear why we'd want an unsupported attribute to make it through

[appleguy]

@bsmith11 thanks so much for debugging this and taking the time to implement & test a fix! I am bummed this issue slowed down your development, though.

I have to admit that I am not familiar with this CoreText attribute cleansing code and its original or current purpose. It seems like this basically circumvents that for a certain class of CT properties, which I certainly agree shouldn't be filtered out, although it's hard for me to say if this breaks a perhaps even rarer edge case originally intended to be addressed by the attribute cleansing. I think this is better than it was before, so in it goes!