The coordinate system was unable to support types that prohibited
redim or retype operations. Additionally, the `tags' type used for
providing named data parameters was unwiedly.
We remove much of the dependance on template template parameters in the
defined operations and instead define these in terms of a template
specialisation of is_coord.
The tag types were replaced with direct specialisation of the `store'
struct by the primary type, and passing this type through use of the
CRTP.
GCC produces ODR error when including paths of the form './foo' and
'foo' in the same binary. Rather than managing duplication we just
universally pick the absolute form over the relative form.
The annotations were never particularly robust, and weren't used in many
locations (or consistently). And we should be migrating to c++14
annotation syntax anyway. By focusing on writing them all locally we
will be a little more standards compliant, and the attributes should be
more visible.
