#27 Color overlays

Přidání získávání jednobarevných textur na ApplicationAtlasManager, který se postará o jejich dispose.
Dále přidání disposables na AbstracttablexiaScreen pro operace, kdy na screenu vznikne disposable a chceme ho nechat na koneci lifecycle disposenout.

Tímto nahrazeny overlaye u dialogů, game menu a únosu

See merge request !41

Conflicts:
	core/src/cz/nic/tablexia/TablexiaSettings.java
	core/src/cz/nic/tablexia/util/ui/dialog/TablexiaDialog.java

Conflicts:
	core/src/cz/nic/tablexia/TablexiaSettings.java
	core/src/cz/nic/tablexia/util/ui/dialog/TextDialog.java

Dialog transparent background, closing dialogs on outside click

Merge into devel after succesfull merge into feature-dialog.

See merge request !37

This reverts commit e0b9abf4.

 * new api for loading texture regions from atlases
 * removed old texture loader
 * gradle tasks for assets preparing
 * gradle UP-TO-DATE task check
 * application new api fix
 * atlases automatic linear filtering
 * sound assets conversion to flat hierarchy
 * automatic global assets loading
 * automatic screen and game local assets loading

 * gradle task for automatic creation of atlases from textures
 * refactored texture directory names