Problem
-------
Currently storage related modifiers use keyword.
Solution
--------
We should use `storageclass` for `private`, `protected`, and `inline`.
See also https://www.sublimetext.com/docs/scope_naming.html#storage
> Keywords that affect the storage of a variable, function or data structure should use the following scope. Examples include static, inline, const, public and private.
Fixes https://github.com/tree-sitter/tree-sitter-scala/issues/127
Problem
-------
Currently our grammar does not support the fewer braces syntax,
which basically lets us pass the last argument as a block after `:`.
Solution
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This implements fewer braces support for call_expression,
infix_expression, with and without the lambda start.
Problem
-------
Currently operator-like identifiers are not part of the simple
expression, so you can't call `::(123)`.
Solution
--------
This includes `$.operator_identifier` into `_simple_expression`,
and further improves the expression hierarchy.
Note that this removes test on double-prefix-expression.
It's not allowed in Scala spec to have double-prefix.