Adapted comment
Added more QML keywords
Improve font-lock detection of property declaration

This should highlight property names now for non builtin types and
for types likes list<xxx>, too.
Improve indentation of single lines

<tab> should not move the cursor to the end-of-line, but to the beginning
of line, if in front of it.  Otherwise don't move the cursor at all.

This is somewhat in line with the behaviour of other major modes.
Rewrite

- based on css mode, which gives us some nice indentation out of the box
- adding more keywords
- changed some font lock regex
- a number of basic commands
- simple abbrev expanding