Fix strand compilation on Windows

Visual (2010 and 2013) does not support enable_if in template arguments. I've
put it as the return type.

Change-Id: Ie8b1735f5f29d12e0b1e4b7a300873c04d435780
Reviewed-on: http://gerrit.aldebaran.lan/46742
Reviewed-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Tested-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Update README

Change-Id: Ie766735bc1fa26c8f9ff6ae23bf262ca14fc5d2b
Reviewed-on: http://gerrit.aldebaran.lan/44195
Reviewed-by: jsuchard <jsuchard@aldebaran-robotics.com>
Tested-by: gerrit
Reviewed-by: pdaouadi <pdaouadi@aldebaran-robotics.com>
Tested-by: pdaouadi <pdaouadi@aldebaran-robotics.com>