Merge branch 'master' of https://github.com/Poles/Poles
Added Parallax Scrolling feature to the text rendering.

Also the current FPS of the game can now be shown by pressing 'f'.
Created Physics component to affect game objects by physics forces.
Merge branch 'rendering' of https://github.com/Poles/Poles into rendering

Conflicts:
	src/core/components/SpriteRenderer.cpp
Multiple camera system.
Implemented rendering order.

Now the elements to render are added to a list where are ordered using its parallax index. A lower index indicates a that must be renderer first, and a higher index to render later, so objects who are nearer to the camera will be renderer later and will be over those with lower parallax index.
Changed rendering order from parallax index to z-index.

Now the rendering order is set by the z-index variable and the parallax index only controls how much the camera movement affects the position of an object.

This abstractions let us to make an static image (parallax index = 0) which can be renderer over all the other objects (high z-index, ie: 99). This can be used for UI elements, for example. It was imposible to archive this with the previous implementation.
Merge branch 'rendering'
.gitignore updated
SDL2 frameworks added to MacOSX
CMakeLists can be called outside root dir
Build-process creates symlink to assets
Removed git ignored files
Merge pull request #27 from Poles/dev-cmake

Initial configuration of CMake
Merge branch 'master' of https://github.com/Poles/Poles
Ignored CMakeLists.txt.user.

This is where Qt Creator saves some settings like breakpoints and build kits to not lose them betweeen sessions.
Merge branch 'master' into physics

Conflicts:
	CMakeLists.txt.user
	Poles.cbp
	src/core/components/Physics.cpp
	src/core/components/Physics.h
	src/game/states/DebugState.cpp
	src/game/states/ParallaxTest.cpp