Update link to Lithium

It lives at http://li3.me now :)
Merge pull request #113 from bobthecow/patch-8

Update link to Lithium
Fix project name and link

The link to Wikidata was wrong, since this is a website, not the software.
Wikibase is to Wikidata what MediaWiki is to Wikipedia.
Merge pull request #114 from JeroenDeDauw/wb

Fix project name and link
Update index.md to add PSR-4

Add PSR-4 to list of accepted PSRs on http://www.php-fig.org/psr/ page.
Remove mention of Packagist.
Merge pull request #121 from Crell/remove-packagist

Remove mention of Packagist.
Add concrete5 as a member project

Adding an entry as we'd like it to appear since [we've reached quorum](https://groups.google.com/forum/#!msg/php-fig/OI2I8xPz1Qs/0_RZqYfFsikJ) pending official final count.
Merge pull request #122 from KorvinSzanto/patch-1

Add concrete5 as a member project
Force rebuild to pull in latest PSR-0
Merge pull request #126 from philsturgeon/master

Force rebuild to pull in latest PSR-0
Updated submodule reference.
Merge pull request #127 from philsturgeon/update-standards-submodule

Updated submodule reference
Merge pull request #115 from hardyjohnson/patch-1

Update index.md to add PSR-4
Slovenian language added