size_t conflicts when building on 64-bit Linux

[bachmeil]

I get errors on the following lines when compiling on 64-bit Linux (Ubuntu or Fedora, but I assume this is not distro-specific). The problem in all cases is the use of size_t, causing a ulong to be passed as a parameter that should be int.

display.d: Lines 323, 324, 327
more.d: Lines 399, 402

Importing std.conv and adding to!int as needed fixed the problem in all cases. I'd have submitted a PR, but I don't know if this is how you want to fix it.