Fix markdown highlighting with "C#"

Also fixes for "F#"

src/vs/languages/markdown/common/markdown.ts

@@ -73,10 +73,10 @@ export const language =
 				[/^(\t|[ ]{4})[^ ].*$/, markdownTokenTypes.TOKEN_BLOCK],
 
 				// code block (3 tilde)
-				[/^\s*~{3}\s*((?:\w|[\/\-])+)?\s*$/, { token: markdownTokenTypes.TOKEN_BLOCK, next: '@codeblock' }],
+				[/^\s*~{3}\s*((?:\w|[\/\-#])+)?\s*$/, { token: markdownTokenTypes.TOKEN_BLOCK, next: '@codeblock' }],
 
 				// github style code blocks (with backticks and language)
-				[/^\s*```\s*((?:\w|[\/\-])+)\s*$/, { token: markdownTokenTypes.TOKEN_BLOCK, next: '@codeblockgh', nextEmbedded: '$1' }],
+				[/^\s*```\s*((?:\w|[\/\-#])+)\s*$/, { token: markdownTokenTypes.TOKEN_BLOCK, next: '@codeblockgh', nextEmbedded: '$1' }],
 
 				// github style code blocks (with backticks but no language)
 				[/^\s*`{3}\s*$/, { token: markdownTokenTypes.TOKEN_BLOCK, next: '@codeblock' }],