add dependency M2Crypto and cryptography

Signed-off-by: Florian Brandes <florian.brandes@posteo.de>

devenv.nix

@@ -10,7 +10,7 @@
   # env.GREET = "devenv";
 
   # https://devenv.sh/packages/
-  packages = [ pkgs.file ];
+  packages = [ pkgs.file pkgs.swig4 pkgs.openssl ];
 
   # https://devenv.sh/scripts/
   # scripts.hello.exec = "echo hello from $GREET";

requirements.txt

@@ -1,3 +1,5 @@
 aiosmtpd
 aiosmtplib
 envelope
+M2Crypto
+cryptography