Merge #7809: depends: some base fixes/changes

11d9f6b depends: qt/cctools: fix checksum checksum tests (Cory Fields)
bb717f4 depends: fix "unexpected operator" error during "make download" (Cory Fields)
fe740f1 depends: fix fallback downloads (Cory Fields)
dc4ec6d depends: create a hostid and buildid and add option for salts (Cory Fields)