Animation: Move implementation to cpp file
Introduce file SharedIncludes which includes all common include files

Having this patch applied leads to these timings:
$ time make
real	0m14.372s
user	1m26.200s
sys	0m8.460s

Before I had:
real	0m14.970s
user	1m25.736s
sys	0m9.140s
Remove <iostream> includes as it's covered by shared includes
Move SDL includes to shared includes
Rename SharedIncludes to CommonIncludes
Remove any other occurences of <string> includes
Move <sstream> to CommonIncludes
Sort include lists alphabetically

Also always put the includes (#include "file.h") of flare before
generic includes (#include <file>)

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Remove as many #includes by forward declarations in headers
Move Tooltipdata class to its own file
Have SharedGameResources for unique game classes
Fix compiling with clang++
clang bragged about dead code
Fix crash: We need to construct an EnemyGroupManager when not having a singleton
Remove explicit LootManager variables
Merge branch 'include_reorg' of https://github.com/stefanbeller/flare-engine into include_reorg

Conflicts:
	src/SoundManager.cpp
Merge pull request #2 from dorkster/include_reorg

Fix SoundManager.cpp merge conflict
Merge pull request #664 from stefanbeller/include_reorg

Reorganize header includes, Remove game singletons, have SharedGameResources instead