Enhance the detection of touch.

Currently, if a person provided extra spaces around the colon, then the touch
detection fails.
Take as an example the following media attribute:

    'only screen and (touch-enabled : 0)'

The regexp `MQ_TOUCH` not will capture anything (because of space inserted
before the colon) and then the mediaquerie will be relayed to Moderniz that, if
the browser supports it, test it with `matchMedia`. Howerer, `touch-enabled` is
not standardized, so the result will always be negative.
Merge pull request #11 from piouPiouM/fixes-touch-parsing

Enhance the detection of touch. Thanks @piouPiouM