Add support for RFC 6068 mailto: URL schemes

Test examples from the RFC are also added to the unit tests.

v2: jkt: Fix coding style, remove build failure in the unit tests, don't call
QList::reserve as that isn't available in Qt 4.6 which we still support and fix
the Qt5 build.

REVIEW: 112767
Coding style

Removal of extra spaces and adding curly braces where they IMHO make sense.