Bug 26948 - hyphens incorrectly interpreted as range

Bug 26948 - hyphens incorrectly interpreted as range

This is the kind of easy to fix, hard to review bug. Email validation
make uses of strings listing characters, those strings are then
enclosed between brackets "[]". Inside brackets, the hyphen is used
to describe a range of character [a-d] being a b c d.
The string containing an unescaped hyphen, made JS/PHP validation
to match the incorrect comma ",".

* Backslash hyphen
* JS,PHP: add tests for commas and hyphens in username or domain
* JS: add var to rfc_1034_ldh_str
* JS: minor code cleanup

TESTS:

php phpunit.php -c suite.xml --filter ValidEmail
OK (13 tests, 32 assertions)

Special:BlankPage?action=mwutiltest&debug=true
Ran 66 tests. 66 passed test(s). 0 error(s). 0 partially passed test(s).