Standardized templating logic implementation

[RunDevelopment]

This implements a standardized templating logic and resolves #1991.

The new "language" exposes two functions: createTemplate and tokenizeWithHooks.
While tokenizeWithHooks is just utility which is exposed for convenience, createTemplate is the heart of the PR.

Edit: It now also exposes a replaceWithTemplate function which is basically a generalization of Markup templating (MT). MT is just a thin wrapper around this templating library now.

[RunDevelopment]

Can we merge this?

I can't implement #2403 with Markup Templating alone. In Balde templates, you can escape statements and directives by adding an @ symbol in front of it. To catch this, I need lookbehinds that I don't have in Markup Templating.
While impossible in the current Markup templating, it's trivial to do in the Markup templating of this PR.

@mAAdhaTTah @Golmote

[RunDevelopment]

Closed in favor of #3541.