Add initial support for ExportDeclaration

export function a() { };
export var i = 42;
export let i = 42;
export const i = 42;
Merge branch 'master' of github.com:Constellation/escodegen
Add star to GeneratorExpression
Merge pull request #159 from tuchida/add_star_to_generatorexpression

Add star to GeneratorExpression
Compact generator output support

When compact: true is specified, generator should be formatted as
`function*test(){...}`.
Merge branch 'master' of https://github.com/Constellation/escodegen
Update tests with option.moz.* params