Problem (& Solution) compiling libkdtree++ using Intel Compiler

[Ferdinand Mitterbauer]

Problem:
~~~~~~~~
Building a project using libkdtree++ using Intel C++ Compiler 11.1 (on 
Windows 7, 64bit) results in the following error(s):

[...]\libkdtree++\kdtree++/kdtree.hpp(97): error: expected a declaration
               typename _Cmp = std::less<typename _Acc::result_type>,

[...]\libkdtree++\kdtree++/kdtree.hpp(97): error: expected a ";"
               typename _Cmp = std::less<typename _Acc::result_type>,
			
[... skipped bunch off error messages ... ]

The offending line(s) in kdtree.hpp:
93:  template <size_t const __K, typename _Val,
94:       typename _Acc = _Bracket_accessor<_Val>,
95:	      typename _Dist = squared_difference<typename _Acc::result_type,
96:		  typename _Acc::result_type>,
97:       typename _Cmp = std::less<typename _Acc::result_type>,
98:       typename _Alloc = std::allocator<_Node<_Val> > >
99:    class KDTree : protected _Alloc_base<_Val, _Alloc>


Suggested solution:
~~~~~~~~~~~~~~~~~~~
Insert line "#include <functional>" in file kdtree.hpp
(Maybe Line 70 - right after the line "#include <algorithm>" - would be 
a nice place).

greetings,
Ferdinand