~ehmry/getdns-nim

Use $PKG_CONFIG instead of pkg-config

This is for cross-compilation.
Use new buildNimPackage in shell.nix
Replace "ptr char" with "cstring"
Build with nim2Packages
Add .direnv to .gitignore
Use a different test record
Update direnv to take shell from nixpkgs
Add Tupfile and Direnv for running test
Add Nim idiom procs
Use importc for getdns_bindata type
Rename Nimble file
Some convenience
Initial commit

Just wrapping, no convience procs.