Use uintptr_t for casting pointers to integers

This fixes compilation on mingw-w64 and makes failing tests pass
on MSVC in 64 bit mode.
Remove stray dos newlines

These were added in 4ced8a9e and 9645f380.
Remove the explicit -O3 parameter to nasm in visual studio project files

According to "nasm -h", there is no -O3 parameter at all, and
the highest optimization level (-Ox) is already the default.

The corresponding parameter never was set when building with the
make build system.
Remove the literal CRLF (&#x0D;&#x0A;) within the nasm commands in msvc project files
Merge pull request #646 from mstorsjo/cleanup-msvc-nasm

Clean up the nasm commands in the MSVC project files
Merge pull request #642 from mstorsjo/win64-fix

Use uintptr_t for casting pointers to integers
Merge pull request #644 from mstorsjo/remove-dos-newlines

Remove stray dos newlines