Ported Color3f, Cube, Mesh and MeshGenerator

These classes were ported from Avogadro/OpenQube in preparation for
adding support for molecular orbital and electron density surfaces.

Change-Id: If01f3361e2254bc8d29d211a739fb9cd28fe91f6
Bringing the OpenQube code into Avogadro

This way it can easily reuse the Molecule, Cube and related data
structures, and the IO can be incorporated into a more generic IO API.

Change-Id: I8afd0a05d1183eabe8b7881d077f27426eda43f6
Quantum mechanics integration (molecular orbitals, etc)

Added meshes to the molecule object, added a rendering plugin to display
meshes generated by the quantum output plugin. Added a quantum output
plugin that can read in quantum output files, calculate molecular
orbitals and generate isosurface meshes from the resultant cubes.

Change-Id: Ia48792b7c3dd81793674077bec0f6858d307f3ec
Remove some GPL snippets from the gamessukout reader.

Change-Id: Icc514f7a4be6b9ca4555a70c61b72121a243bb17
Moved the include of color3f

It is needed for the vector containing the optional colors in the mesh.

Change-Id: Ib7f8910a7afac7c4f67f336b2833ebc14404f13c
Merge topic 'quantum-mechanics' into master

80a00ed7 Moved the include of color3f
cf243fdc Remove some GPL snippets from the gamessukout reader.
e0c8c9be Quantum mechanics integration (molecular orbitals, etc)
c98c247a Bringing the OpenQube code into Avogadro
dbbf7062 Ported Color3f, Cube, Mesh and MeshGenerator