Add configure-time checks on compiler and STL features, and use the results of those in macros in Fruit code, instead of checking for specific compilers and/or versions.
Also change includes in Fruit headers to be absolute instead of relative.
diff --git a/include/fruit/impl/meta/pair.h b/include/fruit/impl/meta/pair.h
index 372f698..00fd782 100644
--- a/include/fruit/impl/meta/pair.h
+++ b/include/fruit/impl/meta/pair.h
@@ -17,7 +17,7 @@
#ifndef FRUIT_META_PAIR_H
#define FRUIT_META_PAIR_H
-#include "basics.h"
+#include <fruit/impl/meta/basics.h>
namespace fruit {
namespace impl {