Reverted: 2e099caceb9..21102938e8ccb
I'm going to reapply some of them soon, but it's easier to revert them
all first, as there are conflicts. Also the number of changes that were
inserted since then, mean that there would be a huge gap between related
changes.
immutability of the pointed-to type via const qualification. The
pointee of a proxy-based iterator will be const qualified unless a
mutable reference to the value_type can be bound to the returned
proxy.
Added a test for pointee
Fixed iterator_facade so operator[] result type computation didn't
cause a problem with abstract types.
Updated iterator_facade operator[] docs for accuracy.
Allowed Borland to simply fail the indirect_iterator_member_types test
because of its lame const-dropping, instead of trying to work around
it.
[SVN r21579]
