* lib/matrix/eigenvalue_decomposition: Fix eigensystem with complex
  eigenvectors. Patch by pypypy567.
  [Bug #7208] [ruby-dev:46251] [rubyspec:242f8e55bd]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38799 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Update Changelog for r38797

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38800 b2dd03c8-39d4-4d8f-98ff-823fe69b080e