[#1968] Fix IGroupForm docstrings
Update docs for package and source install

Both source install and package install allows solr and postgres to be run on
separate servers.
Fix formatting
Add a note for configuring postgresql
Update Apache and Nginx config to be more modern
Merge branch 'docs-deployment-update' of https://github.com/nigelbabu/ckan into nigelbabu-docs-deployment-update
Merge branch 'nigelbabu-docs-deployment-update'
Merge branch 'IGroupForm-docs' of https://github.com/brew/ckan into brew-IGroupForm-docs
Merge branch 'brew-IGroupForm-docs'