Inconsistent options naming

[bandantonio]

The options below are about headings, not header:

• noHeaderId
• customizedHeaderId
• ghCompatibleHeaderId
• prefixHeaderId
• rawPrefixHeaderId
• rawHeaderId
• headerLevelStart
• tablesHeaderId

Furthermore, as there is one properly named option requireSpaceBeforeHeadingText, I think naming should definitely be updated to keep everything smooth and consistent and to avoid possible confusion.