Document options

[Sindre Sorhus]

It should be easy to see what options are supported and what they do.

Currently you have to dig into the source to find them:

traceur-compiler/src/Options.js

Lines 26 to 62 in 0c3dad3

 annotations: false, 
 arrayComprehension: false, 
 arrowFunctions: true, 
 asyncFunctions: false, 
 blockBinding: true, 
 classes: true, 
 commentCallback: false, 
 computedPropertyNames: true, 
 debug: false, 
 defaultParameters: true, 
 destructuring: true, 
 exponentiation: false, 
 forOf: true, 
 freeVariableChecker: false, 
 generatorComprehension: false, 
 generators: true, 
 memberVariables: false, 
 moduleName: false, 
 modules: 'register', 
 numericLiterals: true, 
 outputLanguage: 'es5', 
 propertyMethods: true, 
 propertyNameShorthand: true, 
 referrer: '', 
 require: false, 
 restParameters: true, 
 script: false, 
 sourceMaps: false, 
 spread: true, 
 symbols: false, 
 templateLiterals: true, 
 typeAssertionModule: null, 
 typeAssertions: false, 
 types: false, 
 unicodeEscapeSequences: true, 
 unicodeExpressions: true, 
 validate: false, 

And the Node interface supports additional options like filename and modules.

[johnjbarton]

https://github.com/google/traceur-compiler/wiki/Options-for-Compiling

The usage message needs to be updated in source.