Completion doesn't work if cursor is not at the end of the word

[Yanpas]

Project is parsed successfully, but if I place cursor in the middle of some name and press autocompletion - the list is wrong.

[matthewmcgarvey]

@fwcd I didn't actually fix this issue if you could re-open it. My PR fixed a different issue around method completions but this is class completions. Seems like there is two problems here:

1. The class isn't being offered as completion (kind of looks like class completions are only being pulled from the kotlin library, do you know if this might be true?)
2. A method is being offered as completion, seems like if the word starts with a capital letter only classes should be considered