Add support for cloning over http

This patch implements basic support for cloning over http, based on the
work on git-http-backend by Shawn O. Pearce.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

ui-clone.h

@@ -0,0 +1,8 @@
+#ifndef UI_CLONE_H
+#define UI_CLONE_H
+
+void cgit_clone_info(struct cgit_context *ctx);
+void cgit_clone_objects(struct cgit_context *ctx);
+void cgit_clone_head(struct cgit_context *ctx);
+
+#endif /* UI_CLONE_H */