Resolves #2396 - create AdaptBuild API

[danielstorey]

#2396

Example implementations:

const AdaptBuild = require('./grunt/api'); // can be derived from package.json:main
const build = new AdaptBuild(); // implied options {outputConfig: 'event'}


// Promise based named task example
build.runTask('build-config').then((output) => {
    console.log(output);
});


// Event based example
build.on('build-config:output', (output) => {
    console.log(output);
});
build.runTask('build-config');


// Hard API example
// At present methods exist for buildConfig, styles & templates
build.buildConfig().then((output) => {
    console.log(output);
});
build.styles().then((output) => {
    console.log(output);
});
build.templates().then((output) => {
    console.log(output);
});

[olivermartinfoster]

closed as very stale