improve(ext/ffi) - allow alias for symbol renames to solve Windows DLL import issues.

[cryptographix]

A number of Microsoft windows DLL's contain two entry points for effectively the same function, with "A" and "W" prefixes to indicate normal (ANSI) or wide strings, for example: winscard.h

The windows import headers .h automatically select between the two variants.

Problem: linux/os-x versions of this library do not have these suffixes, thus making the symbols hash of Deno.dlopen somewhat complicated.

Solution: Add an alias?: string to ForeignFunction, which if set would indicate the symbol name to be imported from the library. This might also help in other cases, such as imported C++ dlls where the symbol names have been munged by the compiler.

[DjDeveloperr]

#13090 implements this (with the only difference being new property is name instead of alias)

[cryptographix]

#13090 implements this (with the only difference being new property is name instead of alias)

Ops. Sorry. Did an issue search beforehand but didn't catch it. Thanks!