Shib SP, how to implement an access control plugin

[Cantor, Scott]

> Please find a first draft of a tutorial at
> 
> https://www.lsc-
> group.phys.uwm.edu/wiki/ShibSPAccessControlPluginTutorial

That's great. I would be willing to transfer that into the wiki at some point if you slap a CC license on that. I can change the LIGO references easily enough.

> I am not a C++ programmer so I would be grateful for a review to point
> out where I have used bad form. I can only say it compiles and
> functions as advertised.

It's not a complex enough example to really run into anything. About the only adjustment is that most of the time extensions that are self-contained in a single compilation unit don't need to use a namespace, they should stick everything in:

namespace {
}

That creates an anonymous namespace that will ensure the symbols are unique and won't collide with anything else.

-- Scott