Jump to included files

[sukus21]

This replaces any backslashes with forward slashes in proposed completions for included files.

Additions:

• Adds the ability to ctrl+click on a file link in an include statement, and be brought straight to that file. If a file cannot be found in the include directories, no link shows up. This is just pure convenience, and is something I have personally been missing.

Fixes:

• Completion proposals for included files would use backslashes for directory separators on Windows. This is annoying, as when that gets pasted into the file, you have to manually either escape the backslashes with another backslash, or correct them to forward slashes. I opted to just replace them with forward slashes, to maintain compatibility with other OS'es.

[sukus21]

I marked this as a draft, as I have a few more things I want done on it, before it is ready.

[sukus21]

This is ready for review now.