Merge pull request #1 from membrane/master

Update from original
RoundRobinStrategy: avoiding possible IndexOutOfBounds, and performance optimization by getting Node list 1x instead of 3x.
Code beauty: replaced .size==0 with .isEmpty().
Hostname class initialization: assigning static class variable in constructor is evil. A later execution could interfere with (non-volatile) variable access. And is not necessary.
The class has 4/6 test failures (before and after). I don't fully understand the logic, therefore I won't touch the main code.
RoundRobinStrategy: shortened time of synchronization.
Merge pull request #166 from vlk32/spel

New feature : Spring Expression language as a part of router configuration
Merge branch 'fabiankessler-master'
Merge branch 'master' of https://github.com/membrane/service-proxy
Merge branch 'master' of https://github.com/membrane/service-proxy into private