Validate MarkupLine

[RS-Credentive]

Markup Type	HTML	Markdown
Emphasis (preferred)	text	*text*
Emphasis	text	*text*
Important Text (preferred)	text	**text**
Important Text	text	**text**
Inline code	text	` text `
Quoted Text	text	"text"
Subscript Text	text	~text~
Superscript Text	text	^text^
Image		
Link	text	[text](*url*)