handle/managed: Implement non-copyable handle

This is a generic handle type that holds a resource and uses RAII to
call a user defined function when the resource is destroyed. A future
change will implement a smart file descriptor based on this interface.

A follow up change will implement the copyable version.

Tested:
    Built and run through unit tests.

Change-Id: Ia8da1d662319e8fb58380ed4979bcf1b74f66dfb
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/meson.build b/src/meson.build
index fd56941..6b1fea9 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -18,3 +18,7 @@
 install_headers(
   'stdplus/signal.hpp',
   subdir: 'stdplus')
+
+install_headers(
+  'stdplus/handle/managed.hpp',
+  subdir: 'stdplus/handle')