More comments wanted for basic.p4 about tutorials

[jafingerhut]

As an example of a different P4 program with comments intended for someone brand new to P4, to learn a few things from the comments, you can take a look at this one:

https://github.com/jafingerhut/p4-guide/blob/master/demo1/demo1-heavily-commented.p4_16.p4

It may be more verbose in its comments than you want, but you are welcome to copy any or all of it and adapt it for the tutorials, if you find it helpful.

[jnfoster]

Thanks @jafingerhut!