Issue #141 Add Vagrantfile to automate dev environment

Problem:
There is no automated way to setup a build environment.

Solution:
Use Vagrant to pull an Ubuntu image and install the same
prerequisites used on Travis.

Testing:
Full build on my macintosh.

libuavcan/include/uavcan/util/templates.hpp

@@ -202,7 +202,7 @@ struct EnumMin
 /**
  * Selects larger value
  */
-template <long A, long B>
+template <unsigned long A, unsigned long B>
 struct EnumMax
 {
     enum { Result = (A > B) ? A : B };