Convert VideoModeList to be dynamically allocated as it is a reference counted object.

git-svn-id: https://irrlicht.svn.sourceforge.net/svnroot/irrlicht/branches/releases/1.7@4377 dfc29bdd-3216-0410-991c-e03cc46cb475
fixed getDepthFunction in IQ3Shader which always returned ECFN_EQUAL due to missing break (found by the cppcheck tool)

git-svn-id: https://irrlicht.svn.sourceforge.net/svnroot/irrlicht/branches/releases/1.7@4387 dfc29bdd-3216-0410-991c-e03cc46cb475
Backport const fix for operator -= in both core::list iterators

git-svn-id: https://irrlicht.svn.sourceforge.net/svnroot/irrlicht/branches/releases/1.7@4388 dfc29bdd-3216-0410-991c-e03cc46cb475