Migrate linkcheck views to ModelAdmin

[timobrembeck]

• Add ModelAdmin for Url and Link models
• Delete report view

Fixes #186

[claudep]

I'm not completely against this, but I would not like to lose some UI niceties from the previous layout. Typically, having a Recheck/Ignore buttons just near the affected link is much nicer than having to check a box at the left, go on the top of the page, open a select, chose an action and clicking on the Go button. The view/edit object links are also nice shortcuts.

[timobrembeck]

@claudep I now included buttons into the list, is this how you envisioned it?

[claudep]

It begins to look rather good, however the big problem currently in my opinion is the width of the table. Even with a screen width of >1900 (~1700 with the left tab hidden), the right of the table is not accessible at all, with no horizontal scrollbar, and then the buttons are not visible (unless you make some gym trying to display the right part of the table). I know it's a current problem with the Django admin in general, however in our use case, it's really bad. Do you have an idea to mitigate that issue?

[timobrembeck]

It begins to look rather good, however the big problem currently in my opinion is the width of the table. Even with a screen width of >1900 (~1700 with the left tab hidden), the right of the table is not accessible at all, with no horizontal scrollbar, and then the buttons are not visible (unless you make some gym trying to display the right part of the table). I know it's a current problem with the Django admin in general, however in our use case, it's really bad. Do you have an idea to mitigate that issue?

@claudep I played a bit around with CSS, I think now it's maybe not pretty, but at least usable on small screen resolutions, what do you think?