User can edit shortlink

- Copies over old attributes that were unedited, deletes old url and
  saves new one

- also fixed css bug on link_box
4 jobs for 25-edit-links in 1 minute and 1 second (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #2258
Go-py2.7

00:00:54

passed #2259
Go-py3.4

00:00:58

passed #2260
Go-py3.5

00:00:58

passed #2261
Go-py3.6

00:01:00

73.0%