Julia: String, character, and other improvements

[RunDevelopment]

Julia strings are now greedy. I also reformatted the file.

This fixes #2360.

[RunDevelopment]

I made some other improvements to Julia:

• Added support for a few missing operators and punctuation. It also fixes this.
• Added more constants.
• Improved number pattern.
• Added regex literals.

[cmcaine]

Does this need any other work?

[cmcaine]

Looks like prism doesn't support multiline comments, either, btw :)

#= a comment
over
multiple
lines
=#

Technically, multiline comments can nest, like this, but for syntax highlighting I'm sure you can get away without pairing the delimiters if that's hard to support.

#=
       foo
       #=
       bar
       =#
       still a comment
       =#

[RunDevelopment]

Thanks for telling me about multiline comments. I have no idea about Julia, so this really helps.

Does this need any other work?

Not work but review. The other maintainers are very busy, so there's no one to review my PRs. To solve this, I review my own stuff after some time passed (usually 2 weeks). Not ideal but like every open source project we also don't have enough hands.

Don't worry, it's not been forgotten. I'll merge this in a few days.

[cmcaine]

Great, thanks!

[cmcaine]

Thanks ❤️