meson: Implement MSVC build of static plugins

Hi all,

This MR is to fix the following issues:

• Cargo is at present blissfully unaware of any deps provided by Meson. They expect downstream consumers that need those deps externally to set PKG_CONFIG_PATH to the relevant meson-uninstalled build folders.

• MSVC is unable to link Rust staticlibs both because of missing, undeclared dependencies (the .pc files are not available at configuration time) and also because of duplicated symbols. The static libraries can be surgically separated using a mix of lib.exe incantations, but the rust_eh_personality unwinding handler must be manually renamed using LLVM (Rust's llvm-tools component). Both steps have been implemented

Fixes #512

Fixes #600