Initially add building OpenSceneGraph as extra stuff.
Add building boost.
OpenSceneGraph need SDL1 instead SDL2
Make loop variable local
Accept patches with different levels.
Fix boost patch
Fix patch procedure.
Fix building boost-1.54.0
Fix openscenegraph script
Download all sources from repositories to $UNPACK_DIR
Build minizip with zlib
Small optimization of script
Add Collada DOM for building as prerequisite for OpenSceneGraph
Fix patching zlib
Rewrite zlib build script
Fix make log name when building from subfolder
Fix building zlib
Fix messages
Add boost to PATH and flags
Do some stuff for collada after installing