ICU4C Locale (locid.h) needs std::move operators

The `Locale` class in ICU4C is rather nontrivial in its copy assignment and copy constructor (several mallocs and frees). It seems like a very good candidate for upgrading to C++11 with std::move operators (move constructor and move assignment).

Instances of this class are copied around rather freely within the number formatting code, leading to a lot of unnecessary work.