Intellij-elixir: Add support for `x.{y, z, w}` expression

[KronicDeth]

Port https://github.com/elixir-lang/elixir/commit/a5a29dc47b6f486853eb92adee1281d26df14ccc

[smeevil]

When this error occurs it affects the syntax highlighting as well. For everything below this line it seems that the variables, ignored variables, and parameters are loosing their colouration. If commenting the alias or writing the alias in full, the highlighting is restored. (version 3.0.1.20160520213720)

[KronicDeth]

It makes sense that it would screw up the everything below since the parsing level will generate PsiErrorElements, which stops the higher levels, like the syntax highlighting that is done by the annotators as opposed to the ASTNode level syntax highlighting

[merqlove]

@KronicDeth Hi, this is fixed?
I can't work with 4.0.0, highlighting/autocomplete is failed in 50% of project files within intellij/rubymine + elixir plugin.

[KronicDeth]

@merqlove if it was fixed this issue would have been closed with a pull request (or manually if I forgot to do Fixes #217 in the PR description). It's not closed, so it's not fixed.

[KronicDeth]

@merqlove do you have any open-source projects I can use to test the fix before releasing for your specific use cases. My test cases are normally elixir-lang/elixir, but it hasn't converted to compact aliases really, so it won't make a good test case. Real-world code is better test cases that toy unit tests.

[merqlove]

@KronicDeth yeah, uploaded some my current docker testing project.
https://github.com/merqlove/elixir-docker-compose
Link to file with bug in readme.

[merqlove]

Also just extracted from this app PubSub wrapper.
https://github.com/merqlove/redix_pubsub_fastlane.
Root file has such aliases.