Merge pull request #41 from Pash-Project/method-invocation

Member access
Remove a bunch of unneeded parens.

This was left over from the creation of many `_opt` rules.
Remove a bunch of `new_lines_opt` terms.
Merge `member_access` and `invocation_expression` grammar

As far as I can tell, keeping them separate was causing a Reduce/Reduce error.
Remove `primary_expression` where there's already a `command_argument`.

That's because `command_argument` can already be a `primary_expression`. This was causing a couple reduce/reduce errors.
Remove `string_literal` from `member_name`.

That's because `value` can already be a `string_literal`. This was causing a reduce/reduce error.