bugfix: rwlock didnt work for flushall and readonly

update v2.0.1

add README_CN.md link in README.md

detach AutoPurge thread to avoid run out of virtual memory

PIKA_VERSION -> 1.0.5

add version information to option, starting and InfoCmd

fix bug mario producer status

Merge branch 'branch_ms' of github.com:baotiao/pika into branch_ms

bugfix: limit master wbuf_ to 500M, or it may pollute the sds metainf…

…o when the wbuf_ is grown to 2.1G

Merge branch 'branch_ms' of github.com:baotiao/pika into branch_ms