Cherry-pick 0e70320 (Select icon based on file extension) from `datajoy`

services/web/app/views/project/editor/file-tree.jade

@@ -107,8 +107,7 @@ script(type='text/ng-template', id='entityListItemTemplate')
 				//- Just a spacer to align with folders
 				i.fa.fa-fw.toggle(ng-if="entity.type != 'folder'")
 
-				i.fa.fa-fw.fa-file(ng-if="entity.type == 'doc'")
-				i.fa.fa-fw.fa-image(ng-if="entity.type == 'file'")
+				i.fa.fa-fw(ng-if="entity.type != 'folder'", ng-class="'fa-' + iconTypeFromName(entity.name)")
 				span(
 					ng-hide="entity.renaming"
 				)  {{ entity.name }}

services/web/public/coffee/ide/file-tree/controllers/FileTreeController.coffee

@@ -1,7 +1,7 @@
 define [
 	"base"
 ], (App) ->
-	App.controller "FileTreeController", ["$scope", "$modal", "ide", ($scope, $modal, ide) ->
+	App.controller "FileTreeController", ["$scope", "$modal", "ide", "$rootScope", ($scope, $modal, ide, $rootScope) ->
 		$scope.openNewDocModal = () ->
 			$modal.open(
 				templateUrl: "newDocModalTemplate"

services/web/public/coffee/ide/file-tree/controllers/FileTreeEntityController.coffee

@@ -51,6 +51,17 @@ define [
 
 		$scope.$on "delete:selected", () ->
 			$scope.openDeleteModal() if $scope.entity.selected
+
+		$scope.iconTypeFromName = (name) ->
+			ext = name.split(".").pop()?.toLowerCase()
+			if ext in ["png", "pdf", "jpg", "jpeg", "gif"]
+				return "image"
+			else if ext in ["csv", "xls", "xlsx"]
+				return "table"
+			else if ext in ["py", "r"]
+				return "file-text"
+			else
+				return "file"
 	]
 
 	App.controller "DeleteEntityModalController", [

services/web/public/stylesheets/app/editor/file-tree.less

@@ -52,13 +52,13 @@ aside#file-tree {
 				}
 			}
 
-			i.fa-folder-open, i.fa-folder {
-				color: lighten(desaturate(@link-color, 10%), 5%);
+			i.fa {
+				color: @gray-light;
 				font-size: 14px;
 			}
 
-			i.fa-file, i.fa-image, i.fa-file-pdf-o {
-				color: @gray-light;
+			i.fa-folder-open, i.fa-folder {
+				color: lighten(desaturate(@link-color, 10%), 5%);
 				font-size: 14px;
 			}