Glusterd changes:
With this patch, glusterd creates a socket file in
DATADIR/run/glusterd.socket , and listen on it for cli requests. It
listens for 2 rpc programs on the socket file,
- The glusterd cli rpc program, for all cli commands
- A reduced glusterd handshake program, just for the 'system:: getspec'
  command

The location of the socket file can be changed with the glusterd option
'glusterd-sockfile'.

To retain compatibility with the '--remote-host' cli option, glusterd
also listens for the cli requests on port 24007. But, for the sake of
security, it listens using a reduced cli rpc program on the port. The
reduced rpc program only contains read-only procs used for 'volume
(info|list|status)', 'peer status' and 'system:: getwd' cli commands.

CLI changes:
The gluster cli now uses the glusterd socket file for communicating with
glusterd by default. A new option '--gluster-sock' has been added to
allow specifying the sockfile used to connect. Using the '--remote-host'
option will make cli connect to the given host & port.

Tests changes:
cluster.rc has been modified to make use of socket files and use
different log files for each glusterd.
Some of the tests using cluster.rc have been fixed.

Change-Id: Iaf24bc22f42f8014a5fa300ce37c7fc9b1b92b53
BUG: 980754
Signed-off-by: Kaushal M <kaushal@redhat.com>
Reviewed-on: http://review.gluster.org/5280
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

Since http://review.gluster.org/4556 glusterd is capable of running
many instances of itself on a single system. This patch exploits
that feature and enhances the regression test framework to expose
handy primitives so that test cases may be written to test glusterd
in a cluster.

Usage:

1. Include "$(dirname)/../cluster.rc" to get access to the extensions

2. Call launch_cluster $N where $N is the count of virtual servers

Calling launch_cluster, starts $N glusterds which bind to $N different
IPs and dynamically defines these primitives:

 - Variables $H1 .. $Hn assigned to hostnames of each "server".

 - Variables $CLI_1 .. $CLI_n assigned as commands to run CLI commands
   on the corresponding N'th server.

 - Variables $B1 .. $Bn assigned to the backend directories on each
   "server".

 - Function kill_glusterd, which accepts a parameter - index number of
   glusterd to be killed.

 - Variables $glusterd_1 .. $glusterd_n assigned to the command lines
   to restart the corresponding glusterd, if it was previously killed.

The current set of primitives and functions were implemented with the goal
of satisfying ./tests/bugs/bug-913555.t. The API will be made richer as
we add more cluster test cases

Change-Id: Ieb13ed9f4a72ac0321db0ca0844c7b294145bb32
BUG: 913555
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.org/4566
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>