Fix key already exists bug.
Merge pull request #1798 from vbjay/Portable

Fix key already exists bug.
Fix for #1790.
Submodule GitExtensionsDoc updated

Submodule GitExtensionsDoc:
    > 18d4200 - Change information about where settings are stored.
    < 439e4cb - add section about re-taggin
Update checked property when menu is shown.  This allows the item to be refreshed between instances.
Merge branch 'Portable'
Merge branch 'pr/n1799_vbjay'
Fixed submodule status on diff tab
Check for later version updates only.
We already know it matched so no need to check the string.
Fix compare.
async is a keyword.
Merge pull request #1801 from vbjay/master

Check for later version updates only
Merge pull request #1802 from vbjay/FixBuildErrors

Fix build error
Make settings thread safe.