Look for indexedDB and IDBTransaction in the global scope when initializing the IndexedDB store.
More careful use of window in websql and indexeddb init.
Added guard to fullproof.make_synchro_point to make sure it doesn't call its callback multiple times.
Merge pull request #17 from terrycojones/dont-call-syncho-callback-more-than-once

Dont call syncho callback more than once