chore(markdown): MD040 Fenced code blocks should have a language specified

Signed-off-by: txtsd <thexerothermicsclerodermoid@gmail.com>

libraries/tomlc99/README.md

@@ -150,7 +150,7 @@ call was successful. If so, you may proceed to read the value
 corresponding to the type of the content.
 
 For example:
-```
+```c
 toml_datum_t host = toml_string_in(tab, "host");
 if (host.ok) {
 	printf("host: %s\n", host.u.s);

nix/NIX.md

@@ -2,6 +2,7 @@
 
 To import with flakes use
 ```nix
+{
   inputs = {
     polymc.url = "github:PolyMC/PolyMC";
   };
@@ -10,11 +11,12 @@ inputs = {
 
   nixpkgs.overlays = [ inputs.polymc.overlay ]; ## Within configuration.nix
   environment.systemPackages = with pkgs; [ polymc ]; ##
+}
 ```
 
 To import without flakes use channels:
 
-```
+```sh
 nix-channel --add https://github.com/PolyMC/PolyMC/archive/master.tar.gz polymc
 nix-channel --update polymc
 nix-env -iA polymc
@@ -22,10 +24,12 @@ nix-env -iA polymc
 
 or alternatively you can use
 
-```
+```nix
+{
   nixpkgs.overlays = [
     (import (builtins.fetchTarball "https://github.com/PolyMC/PolyMC/archive/develop.tar.gz")).overlay
   ];
 
   environment.systemPackages = with pkgs; [ polymc ];
+}
 ```