7.5.1 Change description of comments on preprocessor directive lines

"A source line containing a #define, #undef, #if, #elif, #else, #endif, #line, or #endregion directive can end with a single-line comment. Delimited comments (the /\* */ style of comments) are not permitted on source lines containing pre-processing directives."

This is misleading in a number of ways, #region should be matched with #endregion, and #pragma should be considered. Where the text is included, it may not be a comment anyway.

Vladimir to consider how best to address.