Heap doc typos

[driscoll@…]

In http://www.boost.org/doc/libs/1_49_0_beta1/doc/html/boost/heap/d_ary_heap.html, it says one of the policies is boost::heap::mutable with a default of mutable<false>, but of course this should be mutable_. (This error may be on other pages, I didn't look.)

In http://www.boost.org/doc/libs/1_49_0_beta1/doc/html/heap/concepts.html#heap.concepts.mutability in the "The Fixup Interface" section, I'm guessing your code example intends to call the single-argument version of .increase() and .decrease().

(Not sure if the component should be Documentation or heap.)

[timblechmann]

thanks for the proof-reading!