Rebrand: Change Server name

Summary:
Use the name "Phorge" as the defined platform.

Also prepare to rename the core library "phorge" rather then "phabricator" - see next diff.

T15006

Test Plan: Deployed change, tooltip for "Config" shows "Configure Phorge"

Reviewers: O1 Blessed Committers, speck

Reviewed By: O1 Blessed Committers, speck

Subscribers: speck, tobiaswiese, valerio.bozzolan, Matthew

Maniphest Tasks: T15006

Differential Revision: https://we.phorge.it/D25046