Merge pull request #382 from git-marijus/master

provide some info to not local users
externals/discover: try up to 3 times to find a site that actually has content. Then give up until the next queue run.
Merge https://github.com/friendica/red into zpull
check that aside actually exists before querying the html length
Let the site admin choose whether to display the Discover tab.
Merge pull request #385 from solstag/master

Let the site admin choose whether to display the Discover tab.
source routing stuff
make the discover tab enabled by default the first you use the admin panel, though it will be disabled until you use the admin panel.
issue #384
typo
Default discover to on.
Missed one
revise the sandbox
Merge pull request #387 from beardy-unixer/master

Default discover to on
notes widget: jquery.live is deprecated, replacing with jquery.on and binding to focusout, as the input and paste callbacks are a bit wasteful - they are presumably called on every character typed, yet some of these events have gone missing (probably due to having a lot of network calls in quick succession) so hopefully a single save of the workspace on focusout should be more reliable.
Merge https://github.com/friendica/red into pending_merge
issue #378, failure to correctly link tags where one tag contains a substring of the other (depends on the order they are discovered).
photo timestamp was missing from main profile photo url which prevents photo changes from being immediately seen there.
this is a mess and makes a complicated security model that one can probably drive a truck through. It will have to be fixed. It does make youtubes work again.
finish up the source route storage so we can prevent messages from flowing upstream in complicated delivery chains