Setting the binmode layer to ':crlf' seems to do what we want correctly on all platforms. Detect and retain old behavior for old SIGNATURE files so they don't fail verification, but remove Win32 special case since it causes verification failure of some modules.
Other changes:
Set SHA256 as default hash since SHA1 is deprecated.
Fix for RT#126938
Setting the binmode layer to ':crlf' seems to do what we want correctly on all platforms. Detect and retain old behavior for old SIGNATURE files so they don't fail verification, but remove Win32 special case since it causes verification failure of some modules.
Other changes: