LPS-43687 Add javadoc to ExtRepository.java
LPS-43687 Javadoc for dl-repository-shared framework
LPS-43687 run ant format-javadoc
LPS-43687 Make javadoc more consistent with existing javadocs (DLAppService.java) and specify ext repository to make it more clear.
LPS-43687 Improve consistenty adding namespaces
LRDOCS-933 Edit ExtRepository Javadoc
LRDOCS-933 Edit Javadoc
LRDOCS-933 Clarify ExtRepository Javadoc
LRDOCS-933 Edit Javadoc for dl-repository-shared framework
LRDOCS-933 Edit package.html for dl-repository-shared