remove luaotfload.lua from repo

the version in luaotfload.dtx is authoritative as of now;
I apologize in advance for every time I forget to merge back
changes into the dtx ;-)
migrate files from ‘otfl’ to ‘luaotfload’ prefix
make main files recognize the new ``luaotfload-`` prefix
A more simple loadmodule function

Simply using the luatexbase way... May change in the future, but stick with it for now.
Documenting and simplifying ofm font bug handling

Conflicts:
	luaotfload.dtx
Merge branch 'master' of https://github.com/phi-gamma/luaotfload