Fix a typo in an error message for vector initialisation
Type and Base of a Matrix are not compatible, thus be careful what to return in operator=
Add support to initialisation from and converstion to plain Lua tables to Matrix
Add support for multiplication with plain Lua tables to Quaternion
Relax LuaJIT version requirement to 2.0 (from 2.0.1)
Minor simplification of Matrix::init()
Simplify error handling in Segment::__newindex and fix a wrong, hardcoded array size

No segments larger than 3 were used, so the hardcoded array size caused no problems so far