Fix autocorrect for MethodDefParentheses

Before this change, auto-correcting MethodDefParentheses "fixes" the
following code:

    def columnsort array, size
    end

...with:

    def columnsort (array, size)
    end

This change remove the empty space between the method name and the
parameter list.
Merge pull request #682 from skanev/fix-method-def-parentheses-autocorrect

Fix autocorrect for MethodDefParentheses