designer: Find propertyindex file; Split osiris doc

Resolves: #15 (closed)

• Put Osiris documentation into it's own dir in repo
• Install Osiris docs
• Updated designer to look for propertyindex in Osiris docs
• Add runtime install tag to docs (They would get the doc tag, but designer is expecting them installed so it's better to bundle them imo)

Seems like Gitlab isn't keen on showing all of the changes as the changelist is large. In hindsight I should have split it into two separate commits.