Apply a naming rule of GET to show_server method

[GET /resources] methods should be "list_<resource name>s"
or "show_<resource name>", so this patch applies the rule
to show_server method of compute clients.

Partially implements blueprint consistent-service-method-names

Change-Id: I92addd2ad6502fe00395e2b9455de25c2f53d115
21 files changed