Merge fast-schema-check-in-resource-manager [f=1036158] [r=lifeless,therve]
This branch makes ZStormResourceManager's setup a bit faster between subsequent
test runs, by saving timestamps of schema's patch packages and using them to
decide whether to upgrade the schema or not. For example one can set
ZStormResourceManager.schema_stamp_dir to something like /tmp/my-project-zstorm-stamp
to achieve faster and yet safe setups across all project's branches.
Furthermore, it changes ZStormResourceManager.make() to not create all stores
upfront, but lazily, when they are actually used by tests or code under test.