Addded depenendency load tool

Added simple python script that will load needed libraries into
the project folder structure. Most libraries are now not needed to be
present in development system.

prepare_env.py

@@ -0,0 +1,79 @@
+#!/usr/bin/python
+
+# !WARNING! When run, this script will create prepare.lock file, which will indicate that the script has been run before.
+# This is used for automation with CMake, which will run this script if and only if this file does not exists.
+# If you want to run this script again, remove this file manually first.
+
+# Script used for preparing build envirionment. I cannot use submodules, because I cannot specify commit/tag
+# in submodule config. What's more, preparing vulkan SDK is complicated, so a custom scrip is needed for that.
+
+import io
+import re
+import git
+import os
+import requests
+import subprocess
+
+REPO_DIR = os.path.join(os.getcwd(), "third_party")
+
+class Dependency:
+    def __init__(self, name, file: io.TextIOWrapper):
+        self.name = name
+        while 1:
+            line = file.readline().split("=", 1)
+            if len(line) > 1:
+                match line[0].strip():
+                    case "git_url":
+                        self.git_url = line[1].strip()
+                    case "dl_url":
+                        self.dl_url = line[1].strip()
+                    case "tag":
+                        self.tag = line[1].strip()
+                    case "custom_commands":
+                        self.custom_commands = line[1].strip()
+            else:
+                break
+
+    def download(self):
+
+        # Git repository
+        if hasattr(self, "git_url") and self.git_url:
+            repo = git.Repo.clone_from(self.git_url, os.path.join(REPO_DIR, self.name))
+            repo.git.checkout(self.tag)
+        elif hasattr(self, "dl_url") and self.dl_url:
+            response = requests.get(self.dl_url)
+            if response.status_code == 200: # everything went fine
+                open(os.path.join(REPO_DIR, self.name), "wb").write(response.content)
+
+        if hasattr(self, "custom_commands") and self.custom_commands:
+            p = subprocess.Popen(self.custom_commands, shell=True)
+
+
+def main():
+    if not os.path.isdir(REPO_DIR):
+            os.mkdir(REPO_DIR)
+
+    f = open("dependencies.dep", "r")
+    os.chdir(REPO_DIR)
+    while True:
+        line = f.readline()
+
+        if not line:
+            break
+        stripped = line.strip()
+        # Remove comments
+        if stripped.startswith("#"):
+            return
+        uncommented = stripped.split("#", 1)[0]
+        if len(uncommented) == 0:
+            return
+        if uncommented.startswith("["):
+            dep_name = re.search('\[(.*)\]', uncommented).group(1)
+            dep = Dependency(dep_name, f)
+            dep.download()
+
+    f.close()
+
+
+if __name__ == "__main__":
+    main()