fix dotfeatures bug, intended check is 0<=num<=get_num_vectors()
fix dotfeatures bug, intended check is 0<=num<=get_num_vectors()

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