As mentioned in 2d39da5 the usual pattern is that LibFoo provides a Foo
namespace - LibCoreDump doesn't, so this renames CoreDumpReader to
Reader and puts it in the CoreDump namespace. :^)
This commit gets rid of ELF::Loader entirely since its very ambiguous
purpose was actually to load executables for the kernel, and that is
now handled by the kernel itself.
This patch includes some drive-by cleanup in LibDebug and CrashDaemon
enabled by the fact that we no longer need to keep the ref-counted
ELF::Loader around.
