NEXUX-5542: Reformat, no code change.
NEXUS-5542: Fixing cascade operations.

For now, to have same behavior as with NEXUS-5249,
if a member reports IOEx during cascading operation
the whole task will finish (will continue processing
next members) but method invocation, and hence the
task will fail.
NEXUS-5542: IT for NEXUS-5249 extended for this case too
NEXUX-5542: Reformat, no code change.
NEXUS-5542: Fixing cascade operations.

For now, to have same behavior as with NEXUS-5249,
if a member reports IOEx during cascading operation
the whole task will finish (will continue processing
next members) but method invocation, and hence the
task will fail.
NEXUS-5542: IT for NEXUS-5249 extended for this case too
NEXUX-5542 template method to perform operations on group members

Signed-off-by: Igor Fedorenko <igor@ifedorenko.com>
Merge remote-tracking branch 'origin/master' into nexus-5542
Merge remote-tracking branch 'origin/nexus-5542-GroupOperation' into nexus-5542

Conflicts:
	plugins/indexer/nexus-indexer-lucene-plugin/src/main/java/org/sonatype/nexus/index/DefaultIndexerManager.java
Merge pull request #768 from sonatype/nexus-5542

NEXUS-5542: Update index task fails if one member gets a SocketTimeoutException