[impr] rename getServices to getIris in Readme example

the code section after the services definitions uses getIris.
replace ServiceClientException with IrisException in example catchError code
replace new ServiceDefinitions with new Iris in getIris
hopefully replace all remaining old names (ServiceDefintions...)
fix list of content
Merge pull request #5 from inc-cloitsch/readme_fix

[impr] rename getServices to getIris in Readme example