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Address c4267 warning on MSVC (#1315)

* Fix #1159 Harmonize the types between the loop counter and the vector of indices

The loop counter is a size_t, but they're stored in a vector-of-int leading to
potential overflow warnings. In order to avoid accidental run-time overflow
this change modifies the vector type, rather than the loop counter.

* Fix up line endings

* Update AUTHORS

Add Staffan Tjernstrom <staffantj@gmail.com>

Co-authored-by: Staffan Tjernstrom <staffantj@users.noreply.github.com>