Have setup install ninja

In case the user didn't have it.

build.py

@@ -3,7 +3,6 @@ import sys
 import os
 import shutil
 
-from ninja import ninja_syntax
 import util
 import pathlib
 import shutil
@@ -88,7 +87,7 @@ def main(argv):
     if useNinja:
 
         # Use ninja build system to generate a build script.
-        import ninja
+        from ninja import ninja_syntax
         bo = open("build.ninja", "w")
         nw = ninja_syntax.Writer(bo)
 

setup.py

@@ -30,6 +30,13 @@ except ModuleNotFoundError:
     print("Module `elftools` not found. Installing...")
     install("elftools")
 
+try:
+    import ninja
+    print("Found ninja, continuing...")
+except ModuleNotFoundError:
+    print("Module 'ninja' not found. Installing...")
+    install("ninja")
+
 if not os.path.exists("deps"):
     print("Dependency folder not found, downloading...")