v0.17.0

This version changes the associativity of the exponentiation and ternary operators. In most cases this shouldn't affect anyone, but it's technically a breaking change.

• Using the official typescript target for antlr4. (#103)
• Exponentiation is now right associative. a ** (b ** c) (#99)
• Conditional expression is now right associative. a ? (b ? c : d) : (e ? f : g) (#99)