[TW273] - Core/Spells: Move Rake's custom attributes to database
Core/Misc: Fix some static analysis issues

Fix uninitialized values, most of which are false positives, always initialized before being accessed.
Add some asserts and additional NULL checks as sanity checks. Use SpellMgr::EnsureSpellInfo() if the spell id is valid and always supposed to return a valid not-NULL SpellInfo* .
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'truewow/master'
Merge remote-tracking branch 'upstream/master'