NEWS for 0.6.3 (#574)

* NEWS for 0.6.3

* mention breaking

* mention partially set attributes

NEWS.md

@@ -1,6 +1,18 @@
 MathOptInterface (MOI) release notes
 ====================================
 
+v0.6.3 (November 16, 2018)
+--------------------------
+
+- Variables and constraints are now allowed to have duplicate names. An error is
+  thrown only on lookup. This change breaks some existing tests. (#549)
+- Attributes may now be partially set (some values could be `nothing`). (#563)
+- Performance improvements in Utilities.Model (#549, #567, #568)
+- Fix bug in QuadtoSOC (#558).
+- New `supports_default_copy_to` method that optimizers should implement to
+  control caching behavior.
+- Documentation improvements.
+
 v0.6.2 (October 26, 2018)
 ---------------------------