Manual merges, I guess

Merge pull request #18 from preprocess/develop

Refactor to remove hidden dependencies, and add a bunch of improvements from @ircmaxell.

Merge pull request #17 from preprocess/contrib-master

Improve encoding in deferred execution

Merge pull request #16 from preprocess/fix/allow-optimised-autoloader…

…-generation

Allow optimised autoloader generation

Merge pull request #12 from preprocess/feature/replace-formatting-wit…

…h-prettier

Replace formatting with Prettier

Preprocess before custom compilers kick in

Fix PSR-4 autoloading

Merge pull request #10 from preprocess/feature/new-sigil

New sigil

Require environment during custom installation

Merge pull request #5 from preprocess/rewrite

Rewrite to hide dependencies