Add verify to nipap-passwd

Add new feature to nipap-passwd to verify if a username and password is
correct
Use selected VRF on manual prefix add

This fixes an issue where a manually added prefix would end up in the
wrong VRF as the VRF ID from the selected VRF wasn't used.

Fixes #580.
Switch to tabs in nipap.css

We had a mix of tabs and spaces which didn't look good and tabs seems to
be the more popular choice, so we are going with that.
Bootstrapify web UI

Rename CSS class tooltip to tiptip, to avoid a collision with bootstraps
'tooltip' class.

Fix various alignment issues so that the page looks the way it used to
look before using bootstrap!

Fixes #543.
Add VRF tags to db schema

This adds a news column to the database schema to store tags for VRFs,
much like we have tags for prefixes.

DB version has been bumped to version 5!

Part of #484.
Add VRF tags to backend

This adds support for tags for VRFs in the backend. Smart search has
been modified to support using hash (#) to search for VRFs with a tag.

Part of #484.
Add VRF tags in pynipap

Pynipap now supports tags for VRFs!

Part of #484.
Add VRF tags to CLI

CLI support for tags on VRFs, similar to how it works for prefixes.

Part of #484.
Add VRF tags to web UI

This is the final piece of the puzzle for adding tags to VRFs. Web UI
now sports VRF tags similar to how it works for prefixes.

Fixes #484.
Update test case for VRF tags

Fixes #484
Merge pull request #562 from dosomder/467-nipap-passwd-verify

Add verify to nipap-passwd
Merge pull request #581 from plajjan/484-add-vrf-tags

484 add vrf tags
Add pool tags to db schema

This adds a new column to the database to store tags for pools, just
like it's done for prefixes and VRFs!

Part of #566.
Add pool tags to backend

Backend now supports storing tags for pools, just how it's done for
prefixes and VRFs.

Part of #566.
Add pool tags to pynipap

Pynipap now supports tags for pools!

Part of #566.
Add pool tags for CLI

CLI support for tags on VRFs, similar to how it works for prefixes and
VRFs.

Part of #566.
Add pool tags to web UI

Just like prefixes and VRFs, we not got tags on pools!

Part of #566.
Fix test case for pool tags

Fixes #566.
nipapd: change shebang to /usr/bin/env python

The old shebang does not work well with e.g. virtualenvs.
nipap-passwd: change shebang to /usr/bin/env python