This pull request adds the basic support for textured polygons.

    It adds a function to graphics plugins to set texture.
    It enhances itemgra configuration that allows to set a picture to polygon map elements
    Basic support for Qt5 graphics.
    Some example textures added to car layout.
    Texture files have own resource directory.

* add:cmake: add compilation flags to harden the security of navit

* Try to add the compiler flags outside of the GCC condition

* Simplify the addition of compiler flags and do not rely on non-recommended CMake variable

* Is the O2 level of optimization helping the invalid arg detection?

* Leaving the optimization level up to the preference of the person building

Co-authored-by: Stefan Wildemann <metalstrolch@users.noreply.github.com>
Co-authored-by: jkoan <jkoan@users.noreply.github.com>

Co-authored-by: Joseph Herlant <aerostitch@users.noreply.github.com>

https://github.com/navit-gps/navit/pull/877

* Fixing lib detection based on build host for Android builds

* Fixing workaround according to jandegr's proposal

* Fixing subsequent Android builds (where rename fails because of pre-existing renamed files)