New m-pesa adaptor

[aleksa-krolls]

Fill out this template with as much information as you can about the adaptor
you want. You can always come back later and add more detail. Usually we like to
build a minimal "HTTP client" first, with basic http helpers, and then build up
more complex and helpful functions later.

Request

What is the new adaptor you want to build? And at a high-level, what should
this adaptor do?

Example Text:

We want to build a basic adaptor to integrate with the REST API for `App X`, which does [add description].

To start, this adaptor should:
1. handle authentication
2. include a generic GET helper so we can get any resource
3. make it easy to search for particular records and return results in JSON

Credentials

• Login credentials: Provide login credentials to a demo/test/sandbox
  environment.
• Test record(s): Add links or descriptions on how to access test data.
• Authentication method(s): Note if this adaptor should handle specific API
  protocols (e.g., Oauth, API Key), ensure the right access is configured, and
  provide links to relevant app/API documentation.

Example Text:

See LP `CHT Demo Project` for login information for authentication via Basic Auth.
You'll find that there is already some dummy data for `contacts` in the systems to query.

Sample Code

If you like, you can include an example of what job code using your adaptor
might look like

get('/Patients', { query: { limit: 10 }})

Resources

Add links to API docs and any other app docs that might be useful

Logo Links

Add links to where to find the app's logo for the adaptor logo