Remove unused dev dependencies

[gthb]

Remove a bunch of devDependencies that are not used as far as I can tell.

This speeds up npm install quite a bit. On my machine, with a fully populated npm cache, it goes from:

npm install  22.30s user 11.11s system 101% cpu 32.985 total

to:

npm install  15.89s user 7.43s system 81% cpu 28.671 total

and with an empty cache, it goes from:

npm --cache /tmp/empty-cache install  34.46s user 16.34s system 88% cpu 57.436 total

to:

npm --cache /tmp/empty-cache2 install  19.77s user 10.25s system 124% cpu 24.034 total

Accordingly remove "jsx": "react" from tsconfig.json.

[oguimbal]

nice, thanks !