This is the last PR with lots of renaming for `loot-core`!

Hi there, `Peg.js` is unmaintained, so I figure you all would appreciate
if I replaced it with the drop-in replacement of Peggy. This is work I
am breaking out of #918.

Peggy adds new features like source map support that we could use,
although I do not include that in this change-set. It may be useful for
debugging changes to the .pegjs file we have.e

Removing
- Debugger
- `perf-deeets`
- `codemirror`

*   removed usage of babel-preset-jwl-app

* Add @babel/preset-react

* Dedupe loot-core webpack configs

* Swap to parsing using Peggy

* Actually record syntax errors

* Refactor template types

* Add notifications after applying the templates

* “Successfully”

* Try a Nearley grammar

* Revert "Try a Nearley grammar"

This reverts commit 1e11c07b855a492b905f1291c3eadd93f78ac3de.

Not going with this approach since the error messages are inscrutable.

* switch to PEG.js which has slightly better tooling support

* fix parser

* Fix error reporting

* Adjust grammar for better error messages

Also allow spaces between currency symbol and number

* Fix grammar

* Make #template prefix case insensitive

* Trailing commas

* Remove patch-package from loot-core