Merge pull request #2 from mauzo/master

[RT#89843] Here, have a patch :)
Start using strict and warnings in test which means some fixage: declare $callsite1 can $callsite2
Merge branch 'master' of github.com:rocky/Perl-Devel-Callsite
Try adding Perl 5.8.9
Try Perl 5.8 instead of 5.8.9
Add "check" target so I do not have to remember "make test"
Change DynaLoader to XSLoader.

Inheriting from DynaLoader means inheriting from AutoLoader, and this is
not helpful.
Add license to meta specification
Allow debuggers to get the 'real' callsite.

The previous commit introduced a behaviour change: previously, the test
suite failed under the debugger, because a sub called from the debugger
would return a callsite somewhere in the debugger's guts. Changing to
caller_cx will properly skip those stack frames.

On the off-chance that someone might want that information, if callsite
is called in list context from package DB, return a 2-element list,
where the first element is the ordinary callsite and the second is the
real callsite of the current sub.
Document the newly-added callsite level parameter.
Merge remote-tracking branch 'origin/master'

Conflicts:
	Makefile.PL
Document the new DB behaviour.