fix (c) in include files

include/libhashkit-1.0/algorithm.h

include/libhashkit-1.0/basic_string.h

include/libhashkit-1.0/behavior.h

include/libhashkit-1.0/configure.h.in

include/libhashkit-1.0/digest.h

include/libhashkit-1.0/function.h

include/libhashkit-1.0/has.h

include/libhashkit-1.0/hashkit.h

include/libhashkit-1.0/hashkit.hpp

include/libhashkit-1.0/str_algorithm.h

include/libhashkit-1.0/strerror.h

include/libhashkit-1.0/string.h

include/libhashkit-1.0/types.h

include/libhashkit-1.0/visibility.h

include/libmemcached-1.0/alloc.h

include/libmemcached-1.0/allocators.h

include/libmemcached-1.0/analyze.h

include/libmemcached-1.0/auto.h

include/libmemcached-1.0/basic_string.h

include/libmemcached-1.0/behavior.h