Add 'coming soon!' to 1.8" TFT product mention

Author: oclyke

README.md

@@ -26,7 +26,7 @@ Documentation
 
 Products that use this Library 
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-* [SparkFun 1.8 inch TFT Breakout 128x160](https://www.sparkfun.com/products/15143)
+* [SparkFun 1.8 inch TFT Breakout 128x160 (coming soon!)](https://www.sparkfun.com/products/15143)
 
 Version History
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