Merge "Sync select" and "Inner sync select"

[ccfs]

Please merge the 2 add-ons by:

1. Enhance "Sync select" so that the button can be placed in an internal bar
2. Remove "Inner sync select"

Reasons:

1. Duplicated effort in maintaining an inner version
2. "Ignore file extenstions" check box on the "Inner sync select" window has an opposite meaning to a similar check box on "Sync select" window. This causes confusion.
3. "Ignore file extenstions" check box does not work correctly when it is not ticked.