As a stubserver consumer I want to be able to easily maintain stubdata with excel

[jordi133]

Acceptance criteria:

background:
given that the stubserver is started
and there is a file stubdata.csv on the classpath containing: """
key;statuscode;latency;value1;value2
1;200;10;waarde1;een
3;503;200;;
;404;100;;
"""

given that I configured a stub to use as behavior source SimpleExcelStub (with additional configuration as specified below)
when I do a HTTP GET to .../castalia/stubs/simpleexcelstub/1
then I should get a HTTP 200 response containing the following data:
{
"asdasd": "waarde1",
"content": {
"saddasdasdas": "een"
}
}

given that I configured a stub to use as behavior source SimpleExcelStub (with additional configuration as specified below)
when I do a HTTP GET to .../castalia/stubs/simpleexcelstub/2
then after roughly 200 ms I should get a HTTP 503 response

given that I configured a stub to use as behavior source SimpleExcelStub (with additional configuration as specified below)
when I do a HTTP GET to .../castalia/stubs/simpleexcelstub/3
then after roughly 100 ms I should get a HTTP 404 response

[jordi133]

It would be logical for the stub to use a reponse template (could be contained in SimpleExcelStub.scala, could be in a separate .json file):
{
"asdasd": "$value1",
"content": {
"saddasdasdas": "$value2"
}
}

example simpleexcelstub.json
{
"endpoint": "simpleexcelstub",
"behaviorSource": "SimpleExcelStub.scala"
}