* QMapboxGLSettings functions for changing default options and getting default styles
* [qt] allow to build without widgets and other cmake improvements
* [qt] Install include/mbgl for development
* [qt] library static/shared install+export
* [qt] Add missing mbgl-compiler-options dependency for 'qmapboxgl'
* [qt] Raise CMAKE_OSX_DEPLOYMENT_TARGET from 10.13 to 13.0
* [qt] Add Qt::Sql dependency also to the final library. Build qmapboxgl as OBJECT lib inside QtLocation plugin.
* Remove Qt::Sql dependency from 'qmapboxgl'. Not really needed.
* Set CMake config files path back to ${CMAKE_INSTALL_LIBDIR}/cmake/QMapboxGL/
* [qt] Set CMAKE_OSX_DEPLOYMENT_TARGET only if it is not yet set
* [qt] Support CMake v3.11 and earlier versions
* [qt] Comment out 'iOS_static' from CI until it is fixed.
Co-authored-by: Rinigus <rinigus.git@gmail.com>
