added schema namespace
added temp table for pg backend to hold comments
added support for loading in temporary table
Removed method hooks, instead put the dependent method names to be
picked up from the attributes
Add ontology_namespace method in the loader. It uses the ontology
idspace in case default namespace is not set
Merge branch 'feature/pg-obo-loader' into feature/import-stock
Added prune option to ease up cleaning data before every import
Added commandline parameter for data directory
Added methods for look-up of pub & cvterm
Adding loading of data to be imported, before execute, for look-up
Loading strain data, one row at a time. Incomplete