Improvements to Bio.Structure

[jgreener64]

Bio.Structure is now merged and working. I'm opening this issue to act as a discussion point for future development of the module.

I plan to add a few new features which I think should go in the core module:

• Get sequence from the residues in a PDB file (which will link with the other BioJulia stuff).
• Calculate bond angles/dihedrals/Ramachandran plots.
• Calculate contact maps.

And also to do some stuff on performance:

• Benchmark the module against similar packages.
• Speed up particular parts, especially the stage of parsing that goes Vector{Atom} to ProteinStructure.

If anyone has anything else they would like to see, chime in here. For example:

• Parsing of the PDB header, which I can imagine being useful though I have not yet found essential.
• Calculation of protein mass and centre of mass - would need more stringent element parsing.
• Superposition, which I would like to implement long-term but which requires sequence alignments to be integrated in first.

[jgreener64]

Thanks for tagging.