Added MSVC/Windows compatibility to a few recipes (and the main script).

recipes/libbacktrace/recipe.py

@@ -2,6 +2,8 @@
 from SCons.Script import *
 
 def cook(env: Environment, git_ref = 'master') -> dict:
+    if env['COMPILER_FAMILY'] not in ('gcc', 'clang'):
+        env.Error('libbacktrace requires gcc or clang.')
     repo = env.Cook('GitBranch', repo_name = 'libbacktrace', remote_url = 'https://github.com/ianlancetaylor/libbacktrace.git', git_ref = git_ref)
     checkout_root = repo['checkout_root']
     build_result = env.Cook('AutotoolsProject', checkout_root)