Two workers & worker termination (#198)

* Refactoring codecs

* Plugging in new processor

* Fixing decorator

* MozJPEG free issue

* Better worker aborting, and terminate workers that aren't used for 10 seconds

* Better comment

* Ooops, half-typed comment

* Uncommenting problematic line

* Surma fixed it!

* Abstracting WASM initialisation

* Better comment

* Don't need this.

* Adding ticket

* noInitalRun

* Reverting MozJPEG issue demo

* Making a const for worker timeout

* Inline docs

* Bail early rather than nesting

* Addressing nits

src/codecs/mozjpeg/options.tsx

@@ -1,7 +1,7 @@
 import { h, Component } from 'preact';
 import { bind } from '../../lib/initial-util';
 import { inputFieldChecked, inputFieldValueAsNumber } from '../../lib/util';
-import { EncodeOptions, MozJpegColorSpace } from './encoder';
+import { EncodeOptions, MozJpegColorSpace } from './encoder-meta';
 import '../../custom-els/RangeInput';
 
 type Props = {