Make all kind of timeouts hitting Riak configurable

- All configuration items gathered into `riak_cs_config:*_timeout/0`
- Defaults varies from 5 to 60 seconds according to old code
- New items has defaults by 60 seconds defined in `riak_cs.hrl`
- You can set all configurations at once by setting `riakc_timeouts`
  in `riak_cs` section of `app.config`
- Riak client calls that stem from manual operations does not have
  timeout values configurable

 #Please enter the commit message for your changes. Lines starting
Update a few more riak_cs_pbc calls after timeout API changes
Fixup some mecking and general cleanup of riak_cs_gc_single_run_eqc
Update test assertion for cs743_regression_test

The increase in the default timeout for the mapreduce query used to
retrieve storage calculation results causes the previous expectation
of timeout in this test to no longer be valid.  Update the test
assertion to check that the response is not a timeout instead.
Correct error in call to riak_repl_pb_api:get in riak_cs_block_server
Minor changes to address review feedback
Merge pull request #1021 from basho/feature/gh1008-configurable-timeouts

Make all kind of timeouts hitting Riak configurable

Reviewed-by: kellymclaughlin