Partially revert c0ad77d8 "Enhance Eclipse save actions"

Partially revert c0ad77d8 "Enhance Eclipse save actions"

Revert the following save actions which were introduced in c0ad77d8:
- always use braces around blocks
- remove unused imports

Other than I expected save actions are run globally on edited files -
and not only on edited code lines only.

Hence revert the save action "Convert control statement bodies to
blocks" which would affect a large number of code lines not affected by
the change editing some small part of a class. This would generate a
large number of changes which may lead to many unnecessary conflicts.
Total number of affected lines across jgit would be around 10k lines.

Also revert "Remove unused imports" since it erroneously removes imports
of some annotations needed by pgm classes using args4j.

Change-Id: I879a47f68e664129e6124cf25c1ae1f6a2d7a5aa
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>