Added Markdown editor and Javascript code refactoring

assets/js/src/BoardHorizontalScrolling.js

@@ -0,0 +1,53 @@
+Kanboard.BoardHorizontalScrolling = function(app) {
+    this.app = app;
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.execute = function() {
+    if (this.app.hasId("board")) {
+        this.render();
+    }
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.listen = function() {
+    var self = this;
+
+    $(document).on('click', ".filter-toggle-scrolling", function(e) {
+        e.preventDefault();
+        self.toggle();
+    });
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.keyboardShortcuts = function() {
+    var self = this;
+
+    Mousetrap.bind("c", function() {
+        self.toggle();
+    });
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.onBoardRendered = function() {
+    this.render();
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.toggle = function() {
+    var scrolling = localStorage.getItem("horizontal_scroll") || 1;
+    localStorage.setItem("horizontal_scroll", scrolling == 0 ? 1 : 0);
+    this.render();
+};
+
+Kanboard.BoardHorizontalScrolling.prototype.render = function() {
+    if (localStorage.getItem("horizontal_scroll") == 0) {
+        $(".filter-wide").show();
+        $(".filter-compact").hide();
+
+        $("#board-container").addClass("board-container-compact");
+        $("#board th:not(.board-column-header-collapsed)").addClass("board-column-compact");
+    }
+    else {
+        $(".filter-wide").hide();
+        $(".filter-compact").show();
+
+        $("#board-container").removeClass("board-container-compact");
+        $("#board th").removeClass("board-column-compact");
+    }
+};