Fix buttplug error in the license.

Author: baconhand

LICENSE.md

@@ -14,7 +14,7 @@ met:
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
 
-* Neither the name of buttplug nor the names of its contributors may
+* Neither the name of btleplug nor the names of its contributors may
   be used to endorse or promote products derived from this software
   without specific prior written permission.