[Loadouts] Representing 'in-dev' packages inside loadouts.

[Sewer56]

There needs to be a way to mark or treat packages as 'in-dev' inside a loadout.

Namely, the following are desired:

Not Emitting Warnings for Edited Files

The Diagnostics view must not emit warnings for files which have been edited if a mod
is being recognised as 'in-development'.

Compiling External Code Mods

Hitting Build on a DLL Mod should output the mod to the appropriate 'packages'
folder on build completion.

After a build has been complete, the mod manager MUST replace the current version of a mod
with the 'dev' version.