require doxygen version to be compatible with 1.8.6, see issue #2959
require doxygen version to be compatible with 1.8.6, see issue #2959

karlnapf/shogun,lambday/shogun,Saurabh7/shogun,geektoni/shogun,besser82/shogun,besser82/shogun,shogun-toolbox/shogun,Saurabh7/shogun,sorig/shogun,karlnapf/shogun,geektoni/shogun,sorig/shogun,besser82/shogun,lisitsyn/shogun,lambday/shogun,besser82/shogun,lambday/shogun,sorig/shogun,karlnapf/shogun,lisitsyn/shogun,lisitsyn/shogun,geektoni/shogun,lambday/shogun,sorig/shogun,shogun-toolbox/shogun,Saurabh7/shogun,karlnapf/shogun,shogun-toolbox/shogun,lambday/shogun,sorig/shogun,besser82/shogun,lisitsyn/shogun,shogun-toolbox/shogun,karlnapf/shogun,shogun-toolbox/shogun,besser82/shogun,sorig/shogun,lisitsyn/shogun,shogun-toolbox/shogun,Saurabh7/shogun,Saurabh7/shogun,karlnapf/shogun,geektoni/shogun,Saurabh7/shogun,geektoni/shogun,Saurabh7/shogun,geektoni/shogun,lambday/shogun,Saurabh7/shogun,lisitsyn/shogun,Saurabh7/shogun