Improve share list API filtering

1) Added new params for filtering by:
- share network
- snapshot
- volume type
- host
- limit and offset a la pagination
- project id (useful with '--all-tenants')
- metadata*
- extra-specs*
- direction (asc, desc)*
- key of share*

* requires server-side update

2) Added aliases for params, mostly in perspective to avoid mess of underscore
and dash symbols.

3) Updated utils.print_list func to print results as is without reordering.

Implements  blueprint improve-share-list-filtering

Change-Id: I6fe92c5242f18c900e109271f9182bd5ed287b25