Parsing signs in Angle

When copying coordinates from (PDF) papers, the negative sign in a coordinate may be a dash, but can also be an en-dash. The parser should accept as a negative sign a dash, an en-dash, or an em-dash (as falling under the unambiguous category).

"-" (dash) : u"\u002D" (works now)
"–" (en-dash, option-"-" on Mac keyboard) : u"\u2013"
"—" (em-dash, option-shift-"-" on Mac keyboard) : u"\u2014"

I'd have done it myself and issued a pull request, but I don't really know how the parser works.