Use STL's std::sort for sorting

The C library's qsort() function has the disadvantage of needing an indirect
function call for every comparison, and must use many conditional branches to
support varying element sizes.  This is why the code was using a hand-written
sort function prior to this commit.

std::sort() generates unique code for each data type being sorted, and hence is
much more efficient on average.  To avoid tainting the source with too much
C++, we create a separate C++ file just for sorting.  The sorting code
generated by STL is much faster than the pre-existing sorting functions.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
query.c: Support the = operator

This can be used for searching for entries by exact age.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Remove an extraneous empty line

Whitespace only.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>