Labels for bookmarks

[cyberduck]

@dkocher created the issue

Allow color coding bookmarks.

Have an option for each bookmark to
color code it and then show the color in the window VERY clearly. As in
the top bar with the path selector or the column header background or
something big and thick that spans the page.

[cyberduck]

@dkocher commented

Related to #12233.

[cyberduck]

@dkocher commented

Model in e788b7a.

[cyberduck]

@dkocher commented

Allow input for labels in fe3e008.

[cyberduck]

@dkocher commented

We opted to implement this with the option to assign labels as token strings to a bookmark which allows to search by keywords. Later versions will allow to group bookmarks by the assigned label. Currently there is no color coding.