Replace core language HexStrings with library entity

[Nick Treleaven via Digitalmars-d]

On 15/03/2015 19:46, Walter Bright wrote:
> Any other ideas on things that can removed from the core language and
> replaced with library entities?

0b1010 binary literals (even though C++11 supports them)
0xABCD hex literals (but useful for porting C)

Also, there are some things which I think are unnecessary:

/++/ - If we made /**/ nest, /++/ would be unnecessary. It would 
potentially break code, but I think it would always cause a compiler 
error so breakage wouldn't be silent. I think good C code tends to avoid 
having /* /* */ comments (and instead uses #if 0 ... #endif).

q"''" non-nested delimited strings. Delimited strings seem to be quite 
rarely used, but the non-matching form I've never seem in the wild. 
Probably any intended use of these could instead use the q"[]" matching 
form or raw `` or heredoc strings instead.