Exceptions should allow custom hyphenation points as well

[Bram Stein]

Hyphenator.js uses the following syntax for exceptions:
'hyphen, 'hyph-en-na-tion'

I would prefer to not use a dash for specifying hyphenation points in exceptions however. There seems a risk for confusion when compound words are added to the exception list. Right now I think the best solution is to allow both '-' and '=' as hyphenation points. The former for backwards compatibility with Hyphenator.js language files and the latter as recommended syntax.

[Bram Stein]

Fixed per SHA: 520330f