Config:
 * blendConfigs: watchBlender, shimBlender & `build: optimize` specs
 * watchBlender for `after`, `before, `files`

Build:
 * `calcRequireJsConfig` neededDeps, strictDeps, shim
 * fixed: `hasErrors` should not be a cached prop

Bundle:
 * loading dependencies.shim from bower paths
 * fillDepsPaths() after all RCs

ResourceConverter.convert(fileResource, callback) accepts a promise returned, uses When.race for promise|callback
urequire exports 'dependenciesBindingsBlender', 'templateBlender', 'shimBlender', 'watchBlender'
urequire.addBBCreated & findBBCreated

`afterBuild` throw errors handled gracefully