Removed reference to libtiff 3.x

Author: radarhere

docs/installation/building-from-source.rst

@@ -44,7 +44,7 @@ Many of Pillow's features require external libraries:
 
 * **libtiff** provides compressed TIFF functionality
 
-  * Pillow has been tested with libtiff versions **3.x** and **4.0-4.7.0**
+  * Pillow has been tested with libtiff versions **4.0-4.7.0**
 
 * **libfreetype** provides type related services