[FAB-8700] Clarify channel update tutorial leader elec

The gossip leader election section of the channel update tutorial is
vague about whether any settings need to be changed or what setting
the peers are using for EYFN. This CR clarifies that the settings
are already set for EYFN in the docker-compose file and that the section
is included for reference for adding peers to a network beyond the peer
added by EYFN.

Change-Id: I360849c0d344e8ddbf9cf784cbda37b511591d4a
Signed-off-by: Will Lahti <wtlahti@us.ibm.com>
(cherry picked from commit b1e3e77)

Author: wlahti

docs/source/channel_update_tutorial.rst

@@ -490,36 +490,49 @@ its contents.
 Configuring Leader Election
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Newly joining peers are bootstrapped with the genesis block, which does not contain information about the organization
-that is being added in the channel configuration update. Therefore new peers are not able to utilize gossip as
-they cannot verify blocks forwarded by other peers from their own organization until they get the configuration
-transaction which added the organization to the channel. Newly added peers must therefore have one of the following
+.. note:: This section is included as a general reference for understanding
+          the leader election settings when adding organizations to a network
+          after the initial channel configuration has completed. This sample
+          defaults to dynamic leader election, which is set for all peers in the
+          network in `peer-base.yaml`.
+
+Newly joining peers are bootstrapped with the genesis block, which does not
+contain information about the organization that is being added in the channel
+configuration update. Therefore new peers are not able to utilize gossip as
+they cannot verify blocks forwarded by other peers from their own organization
+until they get the configuration transaction which added the organization to the
+channel. Newly added peers must therefore have one of the following
 configurations so that they receive blocks from the ordering service:
 
-1. Utilize static leader mode and configure the peer to be an organization leader:
+1. To utilize static leader mode, configure the peer to be an organization
+leader:
 
 ::
 
-    export CORE_PEER_GOSSIP_USELEADERELECTION=false
-    export CORE_PEER_GOSSIP_ORGLEADER=true
+    CORE_PEER_GOSSIP_USELEADERELECTION=false
+    CORE_PEER_GOSSIP_ORGLEADER=true
 
 
-.. note:: This configuration must be the same for all new peers added to the channel.
+.. note:: This configuration must be the same for all new peers added to the
+channel.
 
-2. Utilize dynamic leader election:
+2. To utilize dynamic leader election, configure the peer to use leader
+election:
 
 ::
 
-    export CORE_PEER_GOSSIP_USELEADERELECTION=true
-    export CORE_PEER_GOSSIP_ORGLEADER=false
+    CORE_PEER_GOSSIP_USELEADERELECTION=true
+    CORE_PEER_GOSSIP_ORGLEADER=false
 
 
-.. note:: Because peers of newly added organization won't be able to form membership view, this option will
-          be similar to the static configuration, as each peer will start proclaiming himself to be a leader.
-          However eventually once they get updated with the configuration transaction that adds the
-          organization to the channel, there will be only one active leader for the organization. Therefore it
-          is recommended to leverage this option if you eventually want the organization's peers to utilize
-          leader election.
+.. note:: Because peers of the newly added organization won't be able to form
+          membership view, this option will be similar to the static
+          configuration, as each peer will start proclaiming itself to be a
+          leader. However, once they get updated with the configuration
+          transaction that adds the organization to the channel, there will be
+          only one active leader for the organization. Therefore, it is
+          recommended to leverage this option if you eventually want the
+          organization's peers to utilize leader election.
 
 
 Join Org3 to the Channel