Allow id parameter to be a string

[malcolmvr]

Made changes to allow the id parameter to be a string.
Create a new test file to test this.
Verified all tests pass.

[coveralls]

Coverage remained the same at 100.0% when pulling 39a52e7 on malcolmvr:master into 0766348 on Kikobeats:master.

[Kikobeats]

I did a bit refactor avoiding introduce a dependency, see 661bd3a

Thanks for that