Merge pull request #297 from ideawu/master

merge master
add expire command
Merge pull request #301 from ideawu/dev

merge dev, add expire command
udpate thanks list
Merge pull request #302 from ideawu/dev

udpate thanks list
move some clients to new place
add bit operations, strlen, substr
1.6.8.8
Merge pull request #308 from ideawu/dev

merge dev, 1.6.8.8
php api add hgetall
Merge pull request #314 from ideawu/dev

php api add hgetall