SOLR implementation

Added few R functions(listed below) for Search functionality in rcloud.support.R file
- pushDataToRedis
- pushDataToSolrFromRedis
- pullDataFromSolr

Made few changes in rcloud_support.js file to enable/handling search related calls {targeted functions listed below}
- notebook_update
- added new : custom_search

Added extra button and div element in main.html to show the search results