gitlab bot: add a class to track review scanning

the code to scan all merge request notes for reviews is getting messy,
going to try moving most of the state into a class. still unsure this is
final

dr_botzo/gitlab_bot/lib.py

@@ -161,3 +161,17 @@ class GitlabBot(object):
                         self.client.update(merge_request, assignee_id=new_approver_obj.id)
                     else:
                         log.warning("no approvers left to approve %s, doing nothing", merge_request.title)
+
+
+class _MergeRequestScanningState(object):
+
+    """Track the state of a merge request as it is scanned and appropriate action identified."""
+
+    def __init__(self):
+        """Set default flags/values."""
+        self.approver_list = []
+
+        self.unlogged_approval_reset = False
+        self.unlogged_approval = False
+        self.needs_reviewer = False
+        self.needs_accepter = False