Rewrite algorithm

Changes:

* Output less entities in places where they aren’t needed.

Features:

* `quote` — Preferred attribute quote to use;
* `quoteSmart` — Use other quote if shorter;
* `preferUnquoted` — Use no quotes if shorter;
* `omitOptionalTags`;
* `collapseEmptyAttributes`;
* `tightSelfClosing` — No space before slash in void elements;
* `tightCommaSeparatedLists`;
* `tightAttributes` — No space between quoted attributes;
* `allowParseErrors` — Smaller size by allowing parse errors;
* `allowDangerousCharacters` — Smaller size by opening up XSS vectors.

Bugs:

* Fix stringification of numeric data attribute (`data-123`
  instead of `data123`).

Refactor:

* Refactor code-style;
* Rewrite tests;
* Remove superfluous dot-files.

Author: wooorm

Diff for: .editorconfig

@@ -2,14 +2,8 @@ root = true
 
 [*]
 indent_style = space
-indent_size = 4
+indent_size = 2
 end_of_line = lf
 charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
-
-[*.{json,remarkrc,eslintrc,sh}]
-indent_size = 2
-
-[*.md]
-trim_trailing_whitespace = false