[TASK] Fix Travis build script

Note: this is an attempt, it may need to be reverted.
[DOC] Change build icon image
[DOC] Change link to main site in README
[DOC] Remove code measure charts
[TASK] Simplify uid/WHERE decision in ContentService
[TASK] Add very basic PHPCI configuration
[TASK] Fix package states file
[TASK] Refactor FluxService methods to dedicated classes