Minor cfg improvements from mtbc/pr-863
Add documentation to the security properties
Move hyperlinks to section headers
Fix list indentation and use internal references for rst generation
Escape Ice property from bin/omero config parse --keys
Add unit test for Ice.xx special handling in bin/omero config parse --keys
Restore help on search properties
Add failing unit test with multiple properties in a block
Fix config_parser for multiple configuration lines
Add missing trailing comma to omero.search.excludes
Add unit test for multiple properties in a block
Always cleanup property if the detect line is not escaped
Move note about omero.search.max_file_size
Fix note markup
Fix config parser to properly recognize Ice namespace
Add top-level comment about generated rst
Strip unnecessary linebreaks/whitespaces from rst generation
Add missing double hash
Move cron format description to the text and use rst replace directive

- Also remove unused omero.data.cron
Clean commented cron brean using deprecated omero.data.cron