Display legend if norewrite
[FEATURE] Add Button to email permalink

Add function createPermalink using currently active theme, visible
layers and visible extent. New button opens a new message in user's mail
client and inserts the permalink into the message body.
Fix #6999 top-most node can be visibleLayers value
Merge pull request #25 from bstroebl/sendURL

[FEATURE] Add Button to email permalink
Merge pull request #26 from bstroebl/fix#6999

Fix #6999 top-most node can be visibleLayers value
Merge pull request #24 from bstroebl/legendThemeSwitcher

Display legend if norewrite
Merge remote branch 'neu/master'