Add error stream.

Repaired scores bug.
Replaced dynamic_cast by static_cast - where it is possible.
Html change
Merge remote-tracking branch 'origin/master' into Zyga_Working_Branch
Merge remote-tracking branch 'origin/gh-pages' into Zyga_Working_Branch
Merge branch 'konkitWorkingBranch'
isEmpty added to collections
Enemies are spawning now in waves