put undefined value instead of null value as IE implementation of indexedDB does not support null values
set loclStorage to undefined when the code is loaded inside a google chrome packaged webapp so it does not throw an exception
using window.chrome instead of typeof(chrome)
remove localStorage initializing to undefined
remove changes related to IE bug
Merge pull request #19 from lejenome/master

support IE implementation of indexedDB and running the code inside a google chrome packaged webapp