Merge the separated link lines on compute client

On current docstring of service clients, every link to API
reference is separated to 2 lines. That is unreadable on the
code and the documentation which is created from the docstring
also will be unreadablebecause of the separated link lines.

This patch merges the separated lines into a single line for the
readability.

Change-Id: I14bc0f75bb8f149ddee1d20f6ac7129756244f93
13 files changed