Moved read_png routine to a separate shared directory.

Added png2numlist resource builder.
Added Matrix3x3.

Multiplication, Scaling, Translation and Rotation seem to work.
Added more verbose messages to makefile.
Tracking *.vert *.frag files as well as *.glsl.
Doing more verbose build messages.
Updated .kateproject file.
Moved content of data/icons into data/textures.
Reworked the translator. Using simple data paths.

Created new Translation class under gui/ .
Loading translations only as needed.
Seems to work ok.

Using a global data_prefix variable that is accessed via extern
in various places, including gui/ .

The data path shall now be passed as the first cmd. argument to the program.