Nuked the lpc-doc submodule (to be replaced with a subtree).

Subtrees are more convenient and if you disagree you're wrong.
Squashed 'lpc-doc/' content from commit 8ea4b7c

git-subtree-dir: lpc-doc
git-subtree-split: 8ea4b7ce38a988a200a421d1713f59f150fc8de2
Merge commit '2a87e4fcdb282053b0eccbd6b24a7461d84747a9' as 'lpc-doc'
Replaced Makefiles with a Ninja build descriptor.
:retab before I start screaming at this horrible formatting.

Mixed indentation (and even more broken than usual due to difference
between amount of spaces and the tab size), tab size 8, tabs used at all
(death to tabs).
Nuked the in-game editor.
Removed direct.