Move all the SQL into its own module to make it easier to port to sqlalchemy
move json stuff into its own module, and take out my hacky fake multi-sql-flavor support, i'll be implementing that with sqlalchemy
First stab at SQLAlchemy backend
docstrings
change usage example to reflect the new dbstring style
oops
misleading
useless comma
Refactored a bunch, to the point where the architecture's a little different. Fixed a bug that made undirected edges seem directed some of the time.
Fix inability to update globals
default to alchemy
Enable use of custom QueryEngine class
Proper transaction control
Fix cursor in sqlite fallback
mend inconsistency of the way graph names were stored
always commit before closing
accept Connection and Engine objects
docstrings
copyright notices
copyright notices