* This commit includes example tutorials and solutions for P4D2 2017.
- Added example P4 programs for ipv4_forwarding, mri, arp, calc
- Added python code to invoke compiler, start bmv2, run mininet
- Added solutions to above programs
- Added README files that describe exercises
* Fix for issue #32. The text had said the name of the action should be ipv4_forward, when it should have been set_dst_info.
