Style: Misc docs and comment style and language fixes

- Removed empty paragraphs in XML.
- Consistently use bold style for "Example:", on a new line.
- Fix usage of `[code]` when hyperlinks could be used (`[member]`, `[constant]`).
- Fix invalid usage of backticks for inline code in BBCode.
- Fix some American/British English spelling inconsistencies.
- Other minor fixes spotted along the way, including typo fixes with codespell.
- Don't specify `@GlobalScope` for `enum` and `constant`.

modules/regex/doc_classes/RegEx.xml

@@ -4,7 +4,7 @@
 		Class for searching text for patterns using regular expressions.
 	</brief_description>
 	<description>
-		A regular expression (or regex) is a compact language that can be used to recognise strings that follow a specific pattern, such as URLs, email addresses, complete sentences, etc. For example, a regex of [code]ab[0-9][/code] would find any string that is [code]ab[/code] followed by any number from [code]0[/code] to [code]9[/code]. For a more in-depth look, you can easily find various tutorials and detailed explanations on the Internet.
+		A regular expression (or regex) is a compact language that can be used to recognize strings that follow a specific pattern, such as URLs, email addresses, complete sentences, etc. For example, a regex of [code]ab[0-9][/code] would find any string that is [code]ab[/code] followed by any number from [code]0[/code] to [code]9[/code]. For a more in-depth look, you can easily find various tutorials and detailed explanations on the Internet.
 		To begin, the RegEx object needs to be compiled with the search pattern using [method compile] before it can be used.
 		[codeblock]
 		var regex = RegEx.new()