fix cvedb import

Author: terriko

cve_bin_tool/VersionSignature.py

@@ -2,7 +2,7 @@
 import sqlite3
 import time
 from datetime import datetime
-from cvedb import DISK_LOCATION_DEFAULT
+from .cvedb import DISK_LOCATION_DEFAULT
 
 
 class VersionSignatureDb:

cve_bin_tool/cli.py

@@ -32,7 +32,7 @@
 from .file import is_binary
 from .OutputEngine import OutputEngine
 
-from .cvedb import CVEDB
+from .cvedb import CVEDB, OLD_CACHE_DIR
 from .log import LOGGER
 
 try: