status/explicit-failures-markup.xml misses tag </library>

[Antony Polukhin]

No closing </library> tag in status/explicit-failures-markup.xml for library unordered:

    <!-- unordered -->
    <library name="unordered">
      <mark-expected-failures>
        <test name="unnecessary_copy_tests"/>
        <toolset name="borland-*"/>
        <toolset name="sun-*"/>
        <note author="Daniel James">
            This tests whether inserting elements creates as few copies as I think
            is possible. If this fails it just means that the container might be
            a little inefficient.
        </note>

      </mark-expected-failures>

    <!-- utility/enable_if -->
    <library name="utility/enable_if">

[Daniel James]

(In [73002]) Unordered: Fix invalid xml. Fixes #5684