Created accept, bind, connect and getsockname wrappers

Created accept, bind, connect and getsockname wrappers in socket.hpp for different protocol families

Review: https://reviews.apache.org/r/28716
Introduced getIP and initialization wrappers for sockaddr_in and addrinfo

Replaced obsolete functions gethostbyname2_r and gethostbyname2 with getaddrinfo
and introduced getIP.  Created initialization wrappers for sockaddr_in and
addrinfo.

Review: https://reviews.apache.org/r/28717
Introduced getIP and created initialization wrappers for sockaddr_in and addrinfo

Replaced obsolete functions gethostbyname2_r and gethostbyname2 with getaddrinfo
and introduced getIP. Created initialization wrappers for sockaddr_in and
addrinfo.

Review: https://reviews.apache.org/r/28718
Introduced getIP and initialization wrappers for sockaddr_in and addrinfo

Replaced obsolete functions gethostbyname2_r and gethostbyname2 with getaddrinfo
and introduced getIP. Created initialization wrappers for sockaddr_in and
addrinfo.

Review: https://reviews.apache.org/r/28719
Fix some style and naming issues
Add Dockerfile for building Mesos from source.

Review: https://reviews.apache.org/r/25369