Support adb client connect to remote server

ADB client: allow user to specify hostname and port number of remote
adb server.
ADB server: bind server to all network interfaces instead of just
localhost when user gives -a flag.

Primary use-case for this change is to support remote testing of USB
devices. HostA is running some test automation software which invokes adb
client. HostB has USB-only device attached and is running adb server. adb
client on HostA makes connection to adb server on HostB to talk to the
USB device.

Change-Id: I845cc8c00350b400317f8c18f813e6fd79bd5470
Signed-off-by: Dean Kwon <daex.i.kwon@intel.com>
Signed-off-by: Jim Bride <jim.bride@intel.com>
Signed-off-by: Matt Gumbel <matthew.k.gumbel@intel.com>