servers: cpp: Clarifiy GetSuitableOSDs interface documentation.

The numberOfOsds paramater is only relevant for grouping policies and will be
ignored by filtering and sorting policies. If a particular number of OSDs is
required by the caller, the returned list has to be reduced by the caller.

This lead to an erorr in the FileScrubber, where every suitable OSD was
assigned to new replicas.
Merge pull request #352 from xtreemfs/jdillmann-suitable_osds_doc

servers: cpp: Clarifiy GetSuitableOSDs interface documentation.
Merge pull request #353 from robert-schmidtke/strict-ssl

Fix build in old environments, disable SSLv2, introduce server-side SSL method setting.
Merge pull request #354 from robert-schmidtke/strict-ssl

Fix Hadoop integration
tests: Fixed Hadoop2 test and changed Hadoop version to 2.6.0
Merge branch 'master' into strict-ssl