:leaves: SiNGA (Simulation of Natural Systems using Graph Automata) is an open-source library containing tools especially for structural bioinformatics and systems biology.
added first stub for parsing of structures from local PDB
introduced LocalPDB object to configure a local PDB installation: this should be extended further to allow configuration of spitted directories, zipped files or not, etc.
if a local file cannot be found, online fetching is tried as fallback
To speed up the parsing for time critical applications we should provide a possibility to parse structures from local distributions.