Enable Quickoffice Editor by default.
Flipped the existing About:flag around such that edting is enabled
by default, and the flag is used to return to a regular vewier.
Made the manifest naming clearer so its easier to see what is what.
In updating the manifest have set the version number of the
component extension to be correct.
This replaces the original CL from dpolukhin which was posted at https://codereview.chromium.org/21629003/