Don't autocomplete closing items (e.g. parenthesis) when the next character is non-whitespace.

[rhdunn]

I often build up code incrementally, so have situations like:

<caret>$test

Where <caret> is the text cursor, at which point I enter foo( (e.g. wrapping a variable in a data or string call). Currently, this autocompletes as:

foo()<caret>$test

The behaviour of the scala plugin is to only auto-insert a ) if the next character is a whitespace character. This should apply to parenthesis, curly brace and closing XML element autocomplete handlers (e.g. when converting a $ret return to <ret>{string($ret)}</ret>).