[connman-qt] Don't hard code library version in project file.

The library version number for libconnman-qt is stored in three
seperate locations: the project file and the two RPM spec files. Remove
the library version number from the project file and instead pass it in
when qmake is called during build.
Merge pull request #122 from amccarthy/library-version

[connman-qt] Don't hard code library version in project file.