Update README.md

Fix License link to no longer 404.
Fixed bug causing incorrectly numbered labels for jumpz in PHP backend
Merge pull request #12 from TazeTSchnitzel/bugfix

Fixed bug causing incorrectly numbered labels for jumpz in PHP backend
Merge branch 'master' of github.com:google/recki-ct into pecl
Merge branch 'pecl' of github.com:google/recki-ct into pecl
More work on PECL compilation
Merge branch 'class_parsing' of github.com:google/recki-ct into pecl
Add compile command
More PECL work, support string concatonation and garbage collection through a free system built by a post-dominator
Fix issue with not freeing constant strings
Fix two issues with compiling, including encoding a string properly, and fixing strlen
Get benchmarks working
Work strings work, allocation and deallocation work, sort-of
Add support for free instruction to PHP compiler
Fix failing test