Allowed digits at the end of method return type

[RichieAHB]

Fixes #153 - includes tests. The regex for type-annotation was looking for [a-zA-Z_$] (the regex used for the first character) as the pattern for the last character rather than [\w$]. There are a few regexes around that allows [.\w$] for the last character of a type name but as far as I can tell, type names can't end with a dot so I've not included this.

I have a plugin that removes whitespace at the end of lines so there are some rogue changes in here that I missed, which can be removed if required.

[msftclas]

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[msftclas]

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[anubmat]

Hi @RichieAHB , this PR is similar to PR #199 . I see you have a good test here. You can either leave some comments on PR #199, or wait for that PR to be merged in and send out a PR to improve those changes.

[mhegazy]

Sorry for the delay. the original issue should be fixed now by #257