Black slightly transparent GUI 1.1

This is a modified ingame gui themed around Black and transparency.
(maybe will finish customising the gui and do main menu gui in a later version).

to install :
-extract content of the "Normal version" folder into your "Starmade/data" folder.
to install the thiner version do the same but then also extract the content of the "Thin version" folder into your "Starmade/data" folder(this version have a small transparency artefact in some window).


Changelog :
-1.1 : Fixed some button color being to much pale