Add list of common values to the docs.

Closes #104.

[ci skip]

Author: bnjmnt4n

platform.js

@@ -1033,6 +1033,9 @@
     /**
      * The name of the browser's layout engine.
      *
+     * The list of common layout engines include:
+     * "Blink", "Edge", "Gecko", "Trident" and "WebKit"
+     *
      * @memberOf platform
      * @type string|null
      */
@@ -1041,6 +1044,11 @@
     /**
      * The name of the product's manufacturer.
      *
+     * The list of manufacturers include:
+     * "Apple", "Archos", "Amazon", "Asus", "Barnes & Noble", "BlackBerry",
+     * "Google", "HP", "HTC", "LG", "Microsoft", "Motorola", "Nintendo",
+     * "Nokia", "Samsung" and "Sony"
+     *
      * @memberOf platform
      * @type string|null
      */
@@ -1049,6 +1057,14 @@
     /**
      * The name of the browser/environment.
      *
+     * The list of common browser names include:
+     * "Chrome", "Electron", "Firefox", "Firefox for iOS", "IE",
+     * "Microsoft Edge", "PhantomJS", "Safari", "SeaMonkey", "Silk",
+     * "Opera Mini" and "Opera"
+     *
+     * Mobile versions of some browsers have "Mobile" appended to their name:
+     * eg. "Chrome Mobile", "Firefox Mobile", "IE Mobile" and "Opera Mobile"
+     *
      * @memberOf platform
      * @type string|null
      */
@@ -1065,6 +1081,11 @@
     /**
      * The name of the product hosting the browser.
      *
+     * The list of common products include:
+     *
+     * "BlackBerry", "Galaxy S4", "Lumia", "iPad", "iPod", "iPhone", "Kindle",
+     * "Kindle Fire", "Nexus", "Nook", "PlayBook", "TouchPad" and "Transformer"
+     *
      * @memberOf platform
      * @type string|null
      */
@@ -1105,7 +1126,7 @@
       /**
        * The family of the OS.
        *
-       * Common values include:
+       * The list of common OS families include:
        * "Windows", "Windows 7 / Server 2008 R2", "Windows Vista / Server 2008",
        * "Windows XP", "OS X", "Ubuntu", "Debian", "Fedora", "Red Hat", "SuSE",
        * "Android", "iOS" and "Windows Phone"