HelpImageDisplayUserControl: move hover text from bottom to top
Add first version of GotoUserManualControl and use it in FormDeleteBranch
FormCreateBranch: add GotoManualControl and fix minimum size
GotoUserManualControl: add tooltip
update GitExtensionsDoc
GotoUserManualControl: switch from tmp doc location to latest online manual
Merge pull request #1739 from feinstaub/topic_help_ui

Add Help link that opens GitExt manual in browser at predefined section