Takes care of proper special member generation globally, fixes #1689

Phew, a lot of classes were affected by this. The rationale for the
changes are as follows:

- When a type X declares any constructor, the default constructor is
  not declared, so there is no need for X() = delete there. In fact,
  there is brutal difference between those two: deleted members
  participate in overload resolution, but not-declared members do not!

- When a type X wants to be non-copyable (e.g. to be only movable, like
  threads, unique_ptrs, and so on), you can either do it by inheriting
  from boost::noncopyable (the old way), or better declare both (!) the
  copy constructor _and_ the copy assignment operator as deleted:

      X(X const&) = delete;
      X& operator=(X const&) = delete;

  We had tons of types with deleted copy constructors that were lacking
  a corresponding deleted copy assignment operator, making them still
  copyable and you wouldn't even notice (read: scary)!

References:

- http://accu.org/content/conf2014/Howard_Hinnant_Accu_2014.pdf
- http://www.boost.org/doc/libs/master/libs/core/doc/html/core/noncopyable.html

Note: I know, I'm quoting Hinnant's extraordinary slides a lot, but
getting the sematic right here is so incredibly important.

include/util/simple_logger.hpp

@@ -29,6 +29,7 @@ class LogPolicy
     static LogPolicy &GetInstance();
 
     LogPolicy(const LogPolicy &) = delete;
+    LogPolicy &operator=(const LogPolicy &) = delete;
 
   private:
     LogPolicy() : m_is_mute(true) {}

include/util/static_rtree.hpp

@@ -106,8 +106,8 @@ class StaticRTree
     boost::filesystem::ifstream leaves_stream;
 
   public:
-    StaticRTree() = delete;
     StaticRTree(const StaticRTree &) = delete;
+    StaticRTree &operator=(const StaticRTree &) = delete;
 
     template <typename CoordinateT>
     // Construct a packed Hilbert-R-Tree with Kamel-Faloutsos algorithm [1]