tabs.sendMessage support

Thanks to @hankchiutw in #123 we now have support for tabs.sendMessage

tabs.reload support

This adds support for tabs.reload

browser.i18n

See #80 and thanks to @Betree we have support for i18n

Notifications API

Thanks to the awesome work by @Kocal in #55 we now support mocks of the notifications API.

Update storage API

Check out the great work done by @AllenFang in #46

Major updates to browser.strorage:

• Return correct value for get function which adapts depending on the parameters of Integer, Array, or Object which can be passed.
• Return correct value for getBytesInUse function which are suppose to return integer.
• Return correct value for set and remove function which are suppose to return nothing.

Initial public release

This is the first version and it still has a long way to go. Hoping I get lots of help from here on out. 😄