Add GUIslice Builder to README (#79)

README.md

@@ -19,6 +19,7 @@
 - Pure C library, no dynamic memory allocation
 - *Widgets*: text, images, buttons, checkboxes, radio buttons, sliders,
   radial controls, scrolling textbox / terminal, graphs, etc. plus extensions and multiple pages.
+- Includes cross-platform **GUIslice Builder** (beta) desktop application to generate layouts
 - *Platform-independent GUI core currently supports*: SDL1.2, SDL2.0, Adafruit-GFX, TFT_eSPI
 - *Devices*: Raspberry Pi, Arduino, ESP8266 / NodeMCU, ESP32, Feather M0 (Cortex-M0), nRF52 (Cortex-M4F), LINUX, Beaglebone Black, M5Stack, STM32
 - *Typical displays*: PiTFT, Waveshare, Adafruit TFT 3.5" / 2.8" / 2.4" / 2.2" / 1.44", OLED 0.96", 4D Cape
@@ -35,6 +36,11 @@
 ![Example 4](http://www.impulseadventure.com/elec/images/guislice-ex08.png)
 ![Example 2](http://www.impulseadventure.com/elec/images/microsdl-ex07.png)
 
+## GUIslice Builder ##
+- Includes cross-platform (Windows & LINUX) desktop application (beta) to generate GUIslice layouts
+- Please refer to [GUIslice Builder wiki](https://github.com/ImpulseAdventure/GUIslice/wiki/GUIslice-Builder) for documentation
+![GUIslice Builder](https://user-images.githubusercontent.com/8510097/48395316-c739be80-e6cb-11e8-9dd6-33336f1fca06.PNG)
+
 
 ## Device Configuration
 - The following table lists a number of devices that have been tested with GUIslice