Optimize lambdas

Uses method references if possible
Removes unnecessary brackets

Using the upcoming JDT cleanup from
https://git.eclipse.org/r/#/c/148248/

Method references are faster in execution and shorter.

Change-Id: I4b8edca1ad34eb1c8788e6729c9bb76f1eefb335
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
26 files changed