Revert "use littleCamelCase for variables"

This reverts commit 3a8df3837d816b84994aba69d2e53c64db46b542.
Revert "rename have_lookup_sources -> has_lookup_sources to be consistent with interface method"

This reverts commit 0109c5881a40addd3c376dab873d0916a6f44aed.
Revert "make default lookup provider private"

This reverts commit 6bba78b9c44e5211bc825c1fa06dda94bf6f42a8.
Revert "fix up struct pointer / interface confusion"

This reverts commit f18413330919cafa7104344435c9c6956a101933.
Revert "rename some methods, implement checks for "first lookupd added", "any lookupds added""

This reverts commit 468e1c878c76fd8d4cdfb243b54a780b72fe77d7.
Revert "add Consumer.SetLookupProvider(), kinda fix some stuff"

This reverts commit 8168db75eda2012f88e66effabf3425366062dd4.
Revert "beginnings of work to make a replaceable LookupProvider"

This reverts commit f97c4eb4593314128736faecfac87301c50f4308.
simple DiscoveryFilter mechanism for Consumer