More major View/Layout changes

Working (more or less):
Adding mods
Deleting mods
Editing mods
Adding mod versions
Rehashing mod versions
Deleting mod versions
Adding builds
Editing builds
Deleting builds (deleting last build has an issue)

Not (recently) tested:
Adding modpacks
Editing modpacks
Deleting modpacks
Adding users
Editing users
Deleting users
Editing solder config

To Do:
Fix forms spacing
Fix "active" and "hover" colouring on the sidebar