Basic Vector framework

Added:

1. Vector core - Vector, VectorAdd, VectorMul, BaseVector
2. BaseScalar
3. Del
4. CoordSysRect
5. Point
6. functions.py - express, matrix_to_vector 
So you mean like <code>orient_new_body</code> etc? Though I am confused as to how these would be incorporated into the <code>\_\_new\_\_</code>. The current format, since it has only one orientation method, allows the corresponding args to be added to the 'new' method directly.