epicov: update front-end to use promises

Need to get GISAID interface working faster

Lines 136 to 138 in e46a672

    
            */ 
        
           function parse_variant(variant, y, cidx, accn, mindate, maxdate) { 
        
             var vdata, pdata = [];

covizu/js/beadplot.js

Lines 365 to 367 in e46a672

    
            */ 
        
           function parse_clusters(clusters) { 
        
             var cluster, variant, coldates, regions, labels,

Node server has been created. Need to fix search functionality

@GopiGugan reports that search interface has been restored
no recombinants in the tree, throws an error for search (#468)

Need to start node server for this instance (run two instances on webserver)
@ArtPoon to make admin account for @nav-mohan on webserver
add rewrite rules to apache configuration to redirect traffic to node server for epicov users
setup pm2

	*/
	function parse_variant(variant, y, cidx, accn, mindate, maxdate) {
	var vdata, pdata = [];

	*/
	function parse_clusters(clusters) {
	var cluster, variant, coldates, regions, labels,