Add account_id column to logs table

When we search for duplicated stanza-ids we have to do it
in the context of an account

gajim/common/check_paths.py

@@ -65,6 +65,7 @@ def create_log_db():
 
             CREATE TABLE logs(
                     log_line_id INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE,
+                    account_id INTEGER,
                     jid_id INTEGER,
                     contact_name TEXT,
                     time INTEGER,

gajim/common/optparser.py

@@ -1044,6 +1044,7 @@ class OptionsParser:
                         oldest_mam_timestamp TEXT,
                         last_muc_timestamp TEXT
                         );
+                    ALTER TABLE logs ADD COLUMN 'account_id' INTEGER;
                     '''
             )
             con.commit()