Fix build against libv8 3.24.5
Make compatible with V8 3.23.11 (and below)
Make compatible with V8 3.23.8 (and below)
Make compatible with V8 3.23.2 (and below)
Update README, removed build badge, require V8 3.22.3

GitHub now caches the build badge image if it is served via HTTP.
However the Jenkins box has no SSL certificate, hence I had to remove
the badge.
Merge pull request #82 from stesie/fix-ftbfs-v8-3.24.5

Fix build against V8 >= 3.24.4
Build fix for GCC 4.4 (eg. el6).
Added checkString() method for checking Javascript syntax.
When passing objects from JS to PHP with mixed keys, some of the keys
might get lost or "re-indexed". This fixes it and adds two tests.
V8 needs to be notified when timezone changes. Keep track of timezone changes and notify it.
Also added a test.
Passing integers that didn't fit in 32-bit integers from PHP to Javascript
did not work properly, now uses float to pass larger numbers.
Forgot to commit test for large number support.
Added new "v8js.use_date" ini setting to convert PHP DateTime objects to Javascript Date objects
when set as V8JS object properties.
Fix passing of null bytes from V8 to PHP (github issue #80).
Make compatible with V8 3.24.10, fixes #83
Clear persistent cells with weak references correctly, refs #88
Make compatible with V8 3.25.12, fixes #88
Merge remote-tracking branch 'rosmo/master'
Fix strdup+getenv behaviour; multi api version support, closes #86
Add null-byte passing test, make var_dump null-byte safe, closes #80