Don't do implicit VRF search for empty string
Don't do implicit VRF search for empty string

If we are not on the prefix list page, don't try to do a prefix search.

If the query string is empty, don't try to do a search either.

Also let explicit = null to the prefix search function mean that it
should use the current value from the URI.

Fixes #305 and #299.

garberg/NIPAP,SoundGoof/NIPAP,ettrig/NIPAP,fredsod/NIPAP,fredsod/NIPAP,bbaja42/NIPAP,SpriteLink/NIPAP,ettrig/NIPAP,bbaja42/NIPAP,SoundGoof/NIPAP,SoundGoof/NIPAP,ettrig/NIPAP,garberg/NIPAP,garberg/NIPAP,SoundGoof/NIPAP,plajjan/NIPAP,garberg/NIPAP,SpriteLink/NIPAP,SpriteLink/NIPAP,fredsod/NIPAP,SpriteLink/NIPAP,plajjan/NIPAP,SpriteLink/NIPAP,ettrig/NIPAP,garberg/NIPAP,ettrig/NIPAP,SoundGoof/NIPAP,fredsod/NIPAP,plajjan/NIPAP,plajjan/NIPAP,bbaja42/NIPAP,garberg/NIPAP,bbaja42/NIPAP,fredsod/NIPAP,fredsod/NIPAP,ettrig/NIPAP,plajjan/NIPAP,bbaja42/NIPAP,SpriteLink/NIPAP,SoundGoof/NIPAP,plajjan/NIPAP,bbaja42/NIPAP