Use bower.json instead of deprecated component.json

Change naming of bower component definition file as per the following note in Bower Github page:

NOTE: In versions of Bower before 0.9.0 the package metadata file was called component.json rather than bower.json. This has changed to avoid a name clash with another tool. You can still use component.json for now but it is deprecated and the automatic fallback is likely to be removed in an upcoming release.