- tables can be created with no engine specified. this will default their engine
to a module-scoped "default engine" which is a ProxyEngine. this engine can
be connected via the function "global_connect".
+- added "refresh(*obj)" method to objectstore / Session to reload the attributes of
+any set of objects from the database unconditionally
- fixed a recursive call in schema that was somehow running 994 times then returning
normally. broke nothing, slowed down everything. thanks to jpellerin for finding this.