How to add a context-sensitive help question-mark icon and hook it up.
Add the help text content to the HelpMessages.properties file:
discussionForum = The Synapse team is happy to announce the release of the new Discussion feature to help your team create a record of communications within your project.
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xmlns:h="urn:import:org.sagebionetworks.web.client.help"
<ui:with field='help' type='org.sagebionetworks.web.client.help.HelpMessages' />
<h:HelpButton href="https://docs.synapse.org/discussionForum" placement="RIGHT">
<ui:text from='{help.discussionForum}'/>
</h:HelpButton>
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