Initial update for component-based approach.
Initial update for component-based approach.

- Added component directive description.

- Added components best practices.

- Added when not to use components.

- Added suggested approach to structure component-based application.

- Added suggested directory structure for component-based application.

- Added routable component architecture based on ui-router module.

beeva-juanmanuelperez/beeva-best-practices,beeva-enriqueotero/beeva-best-practices,beeva-antonioiglesias/beeva-best-practices,beeva-antonioiglesias/beeva-best-practices,beeva-juanmanuelperez/beeva-best-practices