Proposal: explicit invocation syntax

[vknabel]

Introduction
Functions should be called similar to other languages: f(a, b).

Motivation
The current syntax tries to avoid parentheses at all costs and gets confusing and barely unreadable if no highlighting is available.

Proposed Solution
Functions should be called similar to other languages: f(a, b).

This change breaks every file, which can be a benefit during the eager migration as proposed in #48.

data Greeter {
  greet(name)
}

extern print(msg)

func abc(a, b) { }
func abc { a, b => }

abc(a, b)

Variations
Eventually allow the old syntax later for statements and complex invocation expressions only.