core: add hpi query command (#157)

- restructure query code for cli, some test fixes
- initial query_range implementation

    refactored functions in query some more
    to allow re-use in range_range, select()
    pretty much just calls out to a bunch
    of handlers now

tests/core.py

@@ -19,6 +19,7 @@ from my.core.discovery_pure import *
 from my.core.freezer        import *
 from my.core.stats          import *
 from my.core.query          import *
+from my.core.query_range    import *
 from my.core.serialize      import test_serialize_fallback
 from my.core.sqlite         import *
 from my.core.__main__       import *