Added pointless (for now) utils

Enhanced the way entities are drawn

Merge branch 'master' of https://github.com/AdrienJaguenet/OpenEmpires

Added peasant image

Added progress bar

Now entities will (a little more) correctly render

Fixed entities not setting their position correctly

Added GUI text buttons

Changed the way ProtoEntities are stores

Fixed GuiElements unable to handle children of children

Fixed children GuiELement not checking if click inside

Added event handling on gui elements

Fixed SIGSEGV

Fixed SIGSEGV due to parent initializing to itself in GuiLabel constructor

Slightly improved Gui