cache: log about cache hit/miss

cache: log about cache hit/miss

WIP: test only

Merge pull request #1 from charlievieth/go118

update binary parser for go1.18

WIP: add support for new 'G', 'U', and 'P' types

mod: update github.com/charlievieth/buildutil to v0.0.6

update files to use go1.17 build tags

declcache: fix versioned module fallback logic

Due to shadowing we were returning `false` even when we had a match.

handle versioned deps like 'github.com/cev/foo/v2/pkg'

Previously, we only identified versioned dependencies if the version was
at the base of the import path.

modules: update github.com/charlievieth/buildutil to v0.0.5