update comment in testpage boilerplate code

This makes it clear why we override the AMC's callerContext bookCategory value and what the affect is in the various environments (it determines which PAF environment is used).
359: more addComment functionality in the LocalDiscussionMan

Jira: BRIX-359
319: small tweaks to MultiValueQuestion

- removed maxAttempts from multivaluequestion since it is already defined in question
- minor optimization to redrawFeedback_()

Jira: BRIX-319
359: ips-proxy some unit tests for retrieveDiscussionPosts

Jira: BRIX-359
359: fix SubmitManager.handleAddTopicCommentRequest_ referencing wrong properties

Jira: BRIX-359