Support package-local class names

[stevan]

17:42 stevan: just getting sick of stuff like
17:42 stevan: package Foo { class Bar extends Foo::Baz { ... } }
17:42 stevan: in Bar.pm
17:42 doy: yeah, that is kind of annoying
17:42 stevan: package Foo { class Bar extends ..::Baz { ... } }
17:43 stevan: pretty sure nuffin has a module that did that
17:43 stevan: no wait
17:43 stevan: package Foo { class Bar extends .::Baz { ... } }
17:43 stevan: no love?
17:43 stevan: :P
17:43 doy: hmmm
17:44 doy: maybe package Foo { class Bar extends Baz { }; class Quux extends ::DateTime { } }
17:44 doy: look up locally by default, but allow explicitly saying a global lookup
17:44 stevan: hmm
17:44 stevan makes an issue