Provide example C device service

# 🚀 Feature Request

### Relevant Package [**REQUIRED**]

This feature request is for...
edgex-examples

### Description [**REQUIRED**]

Although a number of examples are included in device-sdk-c, these do not include the build infrastructure and other files which would make a good starting point for developing an EdgeX device service in C.

### Describe the solution you'd like

Provide a complete device service example - this can be based on the template in device-sdk-c but should include build files, attribution, readme etc.

### Describe alternatives you've considered