MVE: use pointers for unsafe arithmetic

Iterator arithmetic beyond vector.end() is undefined.
MVE: don't index empty vector
UTIL: don't specialize template for char on WIN32
UTIL: include <algorithm> where necessary
UTIL: use correct form of size_t literals
UTIL: don't try to print stacktrace on WIN32
TESTS: only test enabled image formats
UTIL: implement directory walking for WIN32
UTIL: implement sleep for WIN32
UTIL: support atomic operations on WIN32
MVE: use binary mode for file i/o
MATH: add operator== to algo::InterleavedIter

MSVC needs this for std::copy
MVE: fix erasing view from bundle

iterator is invalidated after refs.erase
DMRECON: fix path names

(must not end with slash for ::_stat)