Fix sqlite default value

urlchecker_cli.py

@@ -12,9 +12,7 @@ def runUrlChecker():
 @click.option(
     "--sqlite",
     "-s",
-    help="The path of the sqlite DB.",
-    default=":memory:",
-    show_default=True,
+    help="The path of the sqlite DB. (default: :memory:)"
 )
 @click.option("--dns", "-d", help="The IP of the DNS server.")
 @click.option("--url", "-u", help="The url to check.")

urlchecker_configuration.py

@@ -25,9 +25,8 @@ def createConfiguration(
         config.read_dict({CONFIG_SECTION: mapping})
 
     # Required values
-    for parameter in ["SQLITE"]:
-        if parameter not in config[CONFIG_SECTION]:
-            raise AttributeError("Config %s not defined" % parameter)
+    if "SQLITE" not in config[CONFIG_SECTION]:
+      config[CONFIG_SECTION]["SQLITE"] = ":memory:"
 
     return config[CONFIG_SECTION]