* use s2geometry's static library

* add geo library, support set/del/search_radial/distance APIs
* integrate the library into redis proxy

* redis_proxy: several bug fix & some refactor

1. fix the thread safety problem when socket is closed
2. when parse error, close the socket instead of abort
3. make the proxy_session & redis_parser's semantic more clear
4. make some rpc codes inline by declare it in source code

*: fix compile error of -Wuninitialized; add --compiler option for build; add --wait_healthy option for start_onebox; speed up build time; update rdsn (#83)

server & shell: update sst size after manual compaction; add --run_seconds for shell count_data; fix pegasus_manual_compact.sh; fix shell config conflict problem; update rdsn (#75)

update rdsn: bug fix of json decode/encode; logging when set/del/clear app envs; change backup policy path on zookeeper (#73)

scripts: not start collector in onebox by default; not exit -1 but exit 0 when test fail; update rdsn (#72)

collector: do not send email when email address is not provided; start collector in onebox; improve config to support collector (#70)

replication: updata rdsn; fix brief_stat_mapper;  add manual_compact.disabled env to disable and cancel manual compaction; refactor pegasus_manual_compact.sh (#66)