Support Multiple application names passed in a request

[doncisco1979]

When providing an application name value as a comma separated list in the config request, the code does not split this and do multiple find operations on each collection (app name) provided.

This could easily be fixed by splitting the name property on ',' and doing a find for each and joining the results. This would allow the use of the config server property spring.cloud.config.name property which allows you to submit multiple names as well as the application name

Input
http://localhost:8080/testapp,supplemental/lablemaker/prod

Expected output
collection name=testapp
profile=prod
label=labelmaker

collection name = supplemental
profile=prod
label=labelmaker

Actual Output
collection name=testapp,supplemental
profile=prod
label=labelmaker