Serial Example for hexiwear

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0:79c0c4cd1ab3
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+++ b/mbed-os.lib	Mon Aug 15 03:58:02 2016 +0000
@@ -0,0 +1,1 @@
+https://github.com/ARMmbed/mbed-os/#0712b8adf6bbc7eb796d5dac26f95d79d40745ef