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.

src/engine/douglas_peucker.cpp

@@ -19,7 +19,6 @@ namespace
 {
 struct CoordinatePairCalculator
 {
-    CoordinatePairCalculator() = delete;
     CoordinatePairCalculator(const util::FixedPointCoordinate coordinate_a,
                              const util::FixedPointCoordinate coordinate_b)
     {

src/server/request_handler.cpp

@@ -147,7 +147,6 @@ void RequestHandler::handle_request(const http::request &current_request,
     catch (const std::exception &e)
     {
         current_reply = http::reply::stock_reply(http::reply::internal_server_error);
-        ;
         util::SimpleLogger().Write(logWARNING) << "[server error] code: " << e.what()
                                                << ", uri: " << current_request.uri;
     }