Move DNSCache from protocol module to common module
Remove Ehcache, replaced with ObjectCache.
Remove spring futures
Remove Proxy Module, add proxy to Dao Module, and add DbProxyFactory
which read proxy information from mysql.
Add Rest Service
add Test class
refactor and add some utils
Delete unuseable file
将conf_detail更改成urllist和host联合主键，因为有些网站的列表页和详细页虽有相同的Host，但它们的解析格式不一样，
urllist 和host确定唯一的解析规则
更改crawler-web功能
更改crawler-core, crawler-slave