Current log prints in this form
```
ERRO[8150] Lock maintenance failed to remove entry for write
lock (should never happen)%!!(MISSING)(EXTRA ....
```
Fix this by using proper formatting directive.
* Rename GenericArgs to AuthRPCArgs
* Rename GenericReply to AuthRPCReply
* Remove authConfig.loginMethod and add authConfig.ServiceName
* Rename loginServer to AuthRPCServer
* Rename RPCLoginArgs to LoginRPCArgs
* Rename RPCLoginReply to LoginRPCReply
* Version and RequestTime are added to LoginRPCArgs and verified by
server side, not client side.
* Fix data race in lockMaintainence loop.