* NSDataDetector
* Add constructor found in header. No idea where the commented-out
constructor came from, it's not in the header, so I removed it.
* Add overloads that take NSTextCheckingType in addition to
NSTextCheckingTypes. Apple's API take NSTextCheckingTypes, but all the
documentation and samples say that you're supposed to pass one or more
or'ed NSTextCheckingType values, so support that as well without casting
between enums.
* NSRegularExpression
* GetMatches had the wrong return type, so add a GetMatches2 that does it
right. Also add a test to make sure it's really right.
* Bind 'regularExpressionWithPattern:options:error:' with a static method.
There's a corresponding constructor, but constructors returning out
NSError parameters isn't the nicest API (when the NSError is important),
so add the static method as well.
* Add a missing [NullAllowed] on FindFirstMatch's return value.
* NSRegularExpressionOptions
* Add missing enum value.
Fixes https://github.com/xamarin/xamarin-macios/issues/5881.
Rolf Bjarne Kvinge