Removed solr from features because cannot save configuration per instance
refs #2519: Moved data dir to a script
Added command line option --skip-migrations to help faster instance setup
refs #2506: Search API is set-up during post_install step
Instance setup is done through php-script
Fixed typo in form name for solr setup
refs #2506: Configuring also apachesolr module
refs #2506: Updated readme with new config.json