add support for Compact series devices (HPMA115C0-xxx)

[climberhunt]

The HPMA115C0 devices add PM1 and PM4 readings, so the message length has changes.

Also:

• Fix example header file name
• Fix sendCmd function prototype to be const instead of unsigned
• Tweak header file to fix typo around ReadParticleMeasurement

Signed-off-by: David Hunt [email protected]