I'm looking for an open source CMS that meets these requirements:
- multi language support (including right to left languages)
- responsive design (mobile friendly)
- open and extensible for further developments (pages as well as database), ability to add my own database (or tables)
- create my own pages accessing the tables
- ability to define different access levels
- ability to handle heavy traffic in the future
- can communicate easily with other systems
- Integration with social network
- fast deployment
- strong developer community and hosting service available.
I know there are a lot of options including WordPress, Joomla, Drupal, etc. I just don't know which one is better for me. I've also heard about WCM like Sitecore. I'm not sure if they work for me or not. I have no problem with technical issues too.