Merge pull request #7 from frensing/patch-1

Update README.md - Fix typo

Author: lathoub

README.md

@@ -56,7 +56,7 @@ will create a instance named `usbMIDI2` (and underlaying MIDI object `MIDI2`) an
 - nRF52832 Bluefruit Feather
 
 ## Memory usage
-The library does not add additional buffers and is extremely efficiant and has a small memory footprint.
+The library does not add additional buffers and is extremely efficient and has a small memory footprint.
 
 ## Other Transport protocols:
 The libraries below  the same calling mechanism (API), making it easy to interchange the transport layer.