Tdewolff-minify

- [JS: fix merging of assignments with let/const declarations,](https://github.com/tdewolff/minify/commit/d0c7dfa1fcffeeacfa1621770b5c0554e89fbcde) [fixes](https://github.com/tdewolff/minify/commit/d0c7dfa1fcffeeacfa1621770b5c0554e89fbcde) https://github.com/tdewolff/minify/issues/474

- [Add MiddlewareWithError and improve error handling of Middleware slightly, see https://github.com/tdewolff/minify/issues/466-](https://github.com/tdewolff/minify/commit/b05e7cb95494bbc589079ca99ab93a639de6d2a4)
- [cmd: add extra check for preserving links when input is a symlink](https://github.com/tdewolff/minify/commit/d1eec07defd0fc154a541b8a360cb3726e2091f5)
- [URL/Data URI: space must be encoded as %20 not + as per RFC3986](https://github.com/tdewolff/parse/commit/7ecf472dc39043f2f4d09bc82c8bcba5add8893c)
- [JS: support parsing of numeric literal separators](https://github.com/tdewolff/parse/commit/ff140b1c713e060ba2a1fc9621a4103e56426548)
- [JS: fix variable renaming for identifier arrow function where identifier was already used](https://github.com/tdewolff/parse/commit/3a696f877e23726368415e6f513bb397e61dd0df)
- [JS: fix walk ClassDecl](https://github.com/tdewolff/parse/commit/6734237d078c9b4efd7a7760a389541c9a5ef7f1)
- [JS: allow strings in import/export statement lists](https://github.com/tdewolff/parse/commit/e4c61639421a49e850b02d9f3293606314be7918)
- [JS: don't remove void expression when it has side effects,](https://github.com/tdewolff/minify/commit/96aaa1291d648fccd23e6ee87eb9271b392714f3) [fixes](https://github.com/tdewolff/minify/commit/96aaa1291d648fccd23e6ee87eb9271b392714f3) https://github.com/tdewolff/minify/issues/463
- JS: fix var declaration order when merging with assignment expressions, fixes https://github.com/tdewolff/minify/issues/472
- [JS: merge sequential var declarations into another declaration](https://github.com/tdewolff/minify/commit/e7fcbe962be6115c98bb8b2d6fdd7fb8f388d6c4)
- [JS: reorder var declaration without default to improve GZIP compression](https://github.com/tdewolff/minify/commit/0b7413df39e5076052bd8c66cc38ee3b0b49d043)
- [JS: clean up var decls that were hoisted, but after merging no longer need hoisting](https://github.com/tdewolff/minify/commit/8c98c9e617aa5d92c06afb30825e11dc727301d1)
- [JS: remove braces for if when nested if statement will be optimized away](https://github.com/tdewolff/minify/commit/064b99a6fd6536587af965a88714b6bef20c76f9)
- [JS: merge assignments with var decls even if variable is already declared and defined in that declaration](https://github.com/tdewolff/minify/commit/b6272e636bd8ae61d4d13fa0c6863c6c47cf98fb)
- [JS: improve conditional and unary-not expression compression](https://github.com/tdewolff/minify/commit/a2eb81a44fab3441f0a15339c8efd8b3ceabd5e3)
- [JS: better compression of if/else statements with return/throw](https://github.com/tdewolff/minify/commit/3ae425a0312e9ce9d12ad338ad9838fafc39da75)
- [JS: improve variable use counting](https://github.com/tdewolff/minify/commit/4532c88bc503bea2d3ec1f13791116b71bdc82df)
- [JS: improve compression for if/else statements with return/throw; and a bugfix](https://github.com/tdewolff/minify/commit/abab01974fd82f91b0b8886fec522c31d1fab0bf)
- [JS: variable declaration bugfix](https://github.com/tdewolff/minify/commit/35944b2ad3ec1012d042b6427017f873ea2d9cd7)
- [JS: improve compression of and/or expressions](https://github.com/tdewolff/minify/commit/ef36774bdeffff478d1ec6db16066dc46f37aa47)
- [SVG: support KeepComments,](https://github.com/tdewolff/minify/commit/66064d2b41d906f112e35455d0c42ac2493e1e0e) [fixes](https://github.com/tdewolff/minify/commit/66064d2b41d906f112e35455d0c42ac2493e1e0e) https://github.com/tdewolff/minify/issues/467

- cmd: fix path errors on Windows, see 450
- cmd: allow absolute paths
- cmd: minifying to same file now more robust in checking if it's the same file
- cmd cmd: fix input/output directories when output is a directory to better match with the behaviour of cp, see 460
- JS: prefer double quotes over single quotes (for GZIP compression)
- JS: support strings in `import` and `export` statements
- JS: revert the reversal of `<` and `<=`, fixes 462

- JS: rewrite `<` and `<=` as `>` and `>=`, slightly improves GZIP compressions
- JS: merge variable declarations and assignments in comma expressions, fixes 455

- JS: parse comma-operator expressions as a list not a tree, fixes 451

- cmd: revert "Add --sequential option to run jobs in serial"
- cmd: don't use concurrency for single tasks
- cmd: refactor read/write code
- JS: rewrite variable renamer to define order of variable names, performance improvement of 3%-4%
- JS: use average character frequency of sample of JS files for variable renaming, reduces GZIP size