Better nickname support

- Username field will not be overwritten with the nickname.
- Mentions work again!
- User chip will show nickname instead of username if present
- Authenticated embed users sidebar nickname support

webapp/titanembeds/database/guild_members.py

@@ -43,3 +43,6 @@ def list_all_guild_members(guild_id):
             "nickname": member.nickname,
         })
     return memlist
+
+def get_guild_member(guild_id, member_id):
+    return db.session.query(GuildMembers).filter(GuildMembers.guild_id == guild_id, GuildMembers.user_id == member_id).first()