Text blocks in Enso grammar for TextMate based editor

[JaroslavTulach]

Pull Request Description

New rules to recognize """ and ''' at the end of line and color everything that's inside nested block of text as string. It properly stops the string literal when nested block ends.

Important Notes

The text mate grammar rules properly end the text block when the block ends. For example in:

main =
    x = """
        a text
    y

a text is properly recognized as string.

Checklist

Please ensure that the following checklist has been satisfied before submitting the PR:

• Screenshots/screencasts have been attached, if there are any visual changes. For interactive or animated visual changes, a screencast is preferred.
• All code follows the style guides.
• All code has been tested:
  • I tried to write a test for the grammar, but failed. Giving up for now.

[JaroslavTulach]

foreign keyword is also painted in green as the line ends with """, but at least the main can follow and is rendered properly:

[Akirathan]

Very good and fast job, thanks! It is certainly much better than it used to be. Finally, all the tests that contains a lot of foreign functions will be rendered (almost) correctly

[radeusgd]

Awesome! Would be cool to get the prefixes working, but it's already an improvement so I probably wouldn't wait on that. I don't have any ideas how to approach this - to do the end marker we need to capture the indentation before prefix, right? So I don't know if there's a way to not make it part of the match.

I have one small request, can we also add this change?

 					"name": "keyword.other",
-					"match": "\\b(here|this|type)\\b"
+					"match": "\\b(here|self|type)\\b"

We got rid of this a loooong time ago and replaced it with self - let's make the grammar reflect that - this is no longer a special keyword.

[JaroslavTulach]

we need to capture the indentation before prefix, right?
I don't know if there's a way to not make it part of the match.

Right. The regexp is correct, but somebody needs to study the TextMate JSON to express that in spite whole line match only the """ is the token.

Or somehow use regexp look behind assertions?

[somebody1234]

i'm not sure lookbehinds are an option here unfortunately, since the leading indentation still needs to be captured

[radeusgd]

I have one small request, can we also add this change?

 					"name": "keyword.other",
-					"match": "\\b(here|this|type)\\b"
+					"match": "\\b(here|self|type)\\b"

We got rid of this a loooong time ago and replaced it with self - let's make the grammar reflect that - this is no longer a special keyword.

I assume we should do this as a follow up PR then?

[JaroslavTulach]

I assume we should do this as a follow up PR then?

Ops. Sorry. I thought I merged the change, but I must have forgotten. Subsequent improvements to official Enso grammar are always welcomed.