Template reporting

[carlhiggs]

This pull requested addresses some minor report formatting aspects raised by Sara Alidoust when reviewing the reports being generated for Brisbane LGA.

Specifically addresses

• Allow option to register separate DOI for policy, spatial and combined reports #520 (report-specific DOIs now possible)
• Citation does not seem to be appearing as report template specific #521 (report-specific citations, had dropped out but now fixed)
• Spatial report intro also refers to policy indicators #522 (spatial report referred to policy indicators in its intro; now fixed)
• Optional 'additional context' info in spatial reports is appearing even if left blank #523 (additional context in spatial report stopped dropping out if left blank; now fixed)