Fixed links to Jira tickets in CMDB's Jira Changes, Problems and
Incidents.
Removed unused import.
Venture's deletion in admin is now disabled; name/symbol cannot be
changed once verified.
Updated changelog.
Merge pull request #626 from xor-xor/t1349

Venture's deletion in admin is now disabled; name/symbol cannot be changed once verified.
Merge pull request #625 from xor-xor/t1372

Fixed links to Jira tickets in CMDB's Jira Changes, Problems and Incidents.
Updated changelog.
Merge pull request #628 from xor-xor/t1349

Updated changelog.
Update CHANGES.rst