added ability to use fontawesome 5 icon on sidebar-toggle

build/less/header.less

@@ -81,6 +81,14 @@
     &:active {
       background: transparent;
     }
+
+    &.fa5 {
+      font-family: "Font Awesome\ 5 Free";
+      &:before {
+        content: "\f0c9";
+        font-weight: 900;
+      }
+    }
   }
   .sidebar-toggle .icon-bar {
     display: none;

dist/css/AdminLTE.css

@@ -263,6 +263,13 @@ a:focus {
 .main-header .sidebar-toggle:active {
   background: transparent;
 }
+.main-header .sidebar-toggle.fa5 {
+  font-family: "Font Awesome\ 5 Free";
+}
+.main-header .sidebar-toggle.fa5:before {
+  content: "\f0c9";
+  font-weight: 900;
+}
 .main-header .sidebar-toggle .icon-bar {
   display: none;
 }

dist/css/alt/AdminLTE-without-plugins.css

@@ -264,6 +264,13 @@ a:focus {
 .main-header .sidebar-toggle:active {
   background: transparent;
 }
+.main-header .sidebar-toggle.fa5 {
+  font-family: "Font Awesome\ 5 Free";
+}
+.main-header .sidebar-toggle.fa5:before {
+  content: "\f0c9";
+  font-weight: 900;
+}
 .main-header .sidebar-toggle .icon-bar {
   display: none;
 }