triAGENS/ArangoDB-PHP#55

optimiser may have mis-optimised duplicate filter statements with limit
fixed firstExample() with `_id` and `_key` attributes
updated documentation about key generators
port to FreeBSD 9.1:
- fixed bits, compile of V8, openssl
- added freebsd section, renamed strings.h to tri-strings.h
- added -lexecinfo for v8
- cleanup operating-system.h
- fixed warning
- fixed wrong include order
- use _WITH_GETLINE to get getline
- removed AI_ALL flag
generated files
added AQL function NEIGHBORS
release version 1.2.3