highlighter: Make it possible to change color of Markdown headers

Fixes #617.

Author: mitya57

ReText/editor.py

@@ -68,6 +68,7 @@
     'htmlStrings':          {'light': '#808000', 'dark': '#d0d070'},
     'htmlComments':         {'light': '#a0a0a4', 'dark': '#b0b0aa'},
     'codeSpans':            {'light': '#505050', 'dark': '#afafaf'},
+    'markdownHeaders':      {'light': '#000000', 'dark': '#ffffff'},
     'markdownLinks':        {'light': '#000090', 'dark': '#8080ff'},
     'blockquotes':          {'light': '#808080', 'dark': '#b0b0b0'},
     'restDirectives':       {'light': '#800080', 'dark': '#d070d0'},

ReText/highlighter.py

@@ -119,7 +119,7 @@ class ReTextHighlighter(QSyntaxHighlighter):
         (reDblUnderline, NF | QFont.Weight.Bold,               Markup.Mkd),
         (reTrpAsterisks, ITAL | QFont.Weight.Bold,             Markup.Mkd),
         (reTrpUnderline, ITAL | QFont.Weight.Bold,             Markup.Mkd),
-        (reMkdHeaders,   NF | QFont.Weight.Black,              Markup.Mkd),
+        (reMkdHeaders,   FG('markdownHeaders') | QFont.Weight.Black, Markup.Mkd),
         (reMkdLinksImgs, FG('markdownLinks'),                  Markup.Mkd),
         (reMkdLinkRefs,  ITAL | UNDL,                          Markup.Mkd),
         (reBlockQuotes,  FG('blockquotes'),                    Markup.Mkd),

configuration.md

@@ -109,6 +109,7 @@ color name        | description
 `htmlStrings`     | string properties inside HTML tags, e.g. `"baz"` inside `<foo bar="baz">`
 `htmlSymbols`     | HTML symbols, e.g. `&bar;`
 `htmlComments`    | HTML comments, e.g. `<!-- comment -->`
+`markdownHeaders` | Markdown headers, e.g. `# Header`
 `markdownLinks`   | Markdown links and images text, e.g. `foo` inside `[foo](http://example.com)`
 `blockquotes`     | blockquotes, e.g. `> quote` in Markdown
 `codeSpans`       | code spans, e.g. `` `code` `` in Markdown