Merge variant from trunk:

 * Fix #7718 (move constructor from template type added)
 * More tests and minor bugfixes
 * Deprecated macros replaced with new ones (thanks to Marshall Clow)


[SVN r81793]

libs/variant

@@ -1 +1 @@
-Subproject commit 3891cde7edec9fd374684dbf1d42be7b03bf377f
+Subproject commit eb17a6afd88d80b5c970dd8bb1729bfdb21c4548