This commit cleans up multiple items with the UPM C example source.
* Switch from usleep and sleep to upm_delay* methods
* Include a mraa_init and check return value prior to using sensor
* All example mains now return
* Added include for mraa.h and upm_utilites.h to all examples
* Reformatted/removed tabs
* Updated author line for the examples I wrote
Signed-off-by: Noel Eck <noel.eck@intel.com>
