HAMA-863: Implement SparseDoubleVector

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1586531 13f79535-47bb-0310-9956-ffa450edef68
HAMA-898: Add DOAP file

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1586533 13f79535-47bb-0310-9956-ffa450edef68
HAMA-899: Add getAdjacentPeerNames() that returns the names of locally adjacent peers

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1590846 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' of https://github.com/millecker/hama; branch 'trunk' of git://git.apache.org/hama into trunk