docs(readme): strikethough systemjs + jspm

make it more obvious that it's not a configuration, but might be in the future

[skip ci]

Author: Awk34

readme.md

@@ -54,7 +54,7 @@ yo angular-fullstack
 **Client**
 
 * Scripts: `JavaScript (Babel)`, `TypeScript`
-* Module Systems: `Webpack`, `SystemJS + JSPM` (maybe)
+* Module Systems: `Webpack`, ~~`SystemJS + JSPM`~~ (maybe)
 * Markup:  `HTML`, `Pug`
 * Stylesheets: `CSS`, `Stylus`, `Sass`, `Less`
 * Angular Routers: `ngRoute`, `ui-router`