Merge pull request #597 from mmklee/bug_fix

Bug fix and factory doumenation
allow assignment: <qring> = <ring>
allow type casts ring -> qring
Better doxygen descriptions
Fix wrong include
Omalloc should not reference itself in include pathes
Better Doxygen settings and descriptions
Updateed doxygen settings and .gitignore
simplify interpreter tables (removed XS(..), INIT_BUG,PROC_BUG)
chg: more checks for one to one correspondence of bi. factors and multi. factors