Change InfluxDB SQL generation template to wrap column names in quoutes

Since column names can contain dots or dashes, which will give syntax errors from InfluxDB API, unless wrapped in quoutes

src/app/services/influxdb/influxdbDatasource.js

@@ -62,7 +62,7 @@ function (angular, _, kbn) {
           query = queryElements.join(" ");
         }
         else {
-          var template = "select [[func]]([[column]]) as [[column]]_[[func]] from [[series]] " +
+          var template = "select [[func]](\"[[column]]\") as \"[[column]]_[[func]]\" from [[series]] " +
                          "where  [[timeFilter]] [[condition_add]] [[condition_key]] [[condition_op]] [[condition_value]] " +
                          "group by time([[interval]]) order asc";