Make MockTagManager compatible with 6.4

great, thanks Stefan!

PR merged

here is a proposal from my side: https://github.com/wcm-io/wcm-io-testing/pull/7

it detects the root path dynamically based on the presence (and value) of a constant com.day.cq.tagging.TagConstants.TAG_ROOT_PATH (which is not available until AEM 6.4 API, but this is detected via reflection).

i get your point. May be we can do the decision based on the presence in the mocked content tree of /etc/tags or /content/cq:tags ?

we need to find a way that makes it compatible for AEM 6.2 .. 6.4 - we do not want to maintain different AEM mock versions for each AEM version.

best thing would be to somehow "auto-detect" if the context is AEM 6.4 or older. maybe the default path to the tag root folder is stored in a constant of the WCM API and we just reference it? then it would be the correct path depending on the WCM API dependencies includes in the project.