Move up to C++14

Change-Id: I9ab6c8537a5b5fd7f0a01848b42886961416011f
Signed-off-by: Zane Shelley <zshelle@us.ibm.com>
diff --git a/meson.build b/meson.build
index 775242d..68a303a 100644
--- a/meson.build
+++ b/meson.build
@@ -3,7 +3,7 @@
         default_options: [
             'warning_level=3',
             'werror=true',
-            'cpp_std=c++11',
+            'cpp_std=c++14',
             'cpp_args=-Wno-unused-parameter'
        ])