stylesheet.scss in binco-4.0.0

- old
+ new

@@ -1,8 +1,17 @@
+// Install bootstrap using yarn
+// $ yarn add bootstrap
+@import "bootstrap_variables";
+@import "bootstrap/scss/bootstrap";
+
+// Install select2 with yarn
+// $ yarn add select2
+@import "select2/dist/css/select2";
+
 @import "binco";