LU-1943 echo: echo_client to get attributes like MDT does

LU-1943 echo: echo_client to get attributes like MDT does

with changes in MDT/MDD the echo_client start working not-correctly,
it uses always 0-stiped files because gets mdsize == 0 from MDD.

- All attributes should be taken explicitely from MDD. Introduce
echo_attr_get_complex() and use it.
- don't use md_getsize_max(), it is not supported anymore.
- fix error handling issues
- remove obsoleted code

Signed-off-by: Mikhail Pershin <tappro@whamcloud.com>
Change-Id: I6f1277018d4b8716aa2e799e99aea6402c04b605
Reviewed-on: http://review.whamcloud.com/4164
Tested-by: Hudson
Reviewed-by: wangdi <di.wang@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>