Fix ascii diagrams with Windows line-endings

[demurgos]

@bcoe reported having issues on Windows due to the ascii range diagrams, possibly related to Windows line endings.

Some regexes are using dotAll mode (/s) when it's not needed, but I think that the core issue is related to how the lines are split. To mitigate the issue, I'll add an editorconfig file enforcing lf line endings, remove the extra /s and fix line splitting.

[bcoe]

@demurgos it wasn't ultimately a Windows issue, we had an older version of Node 8 in our Windows CI that I don't believe yet supported /s, just an FYI.

[demurgos]

Thanks for the clarification. I cleaned up the code slightly and found no link with line endings. Your explanation makes sense (I removed the dotAll flag).