Med minor changes

[ahuangfeng]

Other than that, please find some minor nits to -04:

• s/models defined by the these modules/models defined by these modules
• s/local-binding-supported/local-binding: shorten the name.
• I know Kent uses this for TCP, but no need IMO to prefix groupings with "-grouping". This change would also make statements such as "udp-client-grouping" grouping" read better.
• s/ as an IPv4 address, an IPv6 address, or a hostname/ as an IPv4 address, an IPv6 address, or a domain name
• s/The SHOULD can be ignored when/This MAY be ignored
• s/The "remote-port" leaf/ The "remote-port": I'm picky here but "leaf" is defined per 7950 as "A data node that exists in at most one instance in the data tree", while groupings do not defined any data node.
• s/Defines a generic grouping for UDP-based client applications/Defines a generic grouping for UDP-based clients.
• s/illustrated in Section 3.2 and Section 3.3 defines/ illustrated in Section 3.2 while Section 3.3 defines
• only one grouping is defined here:

OLD:
This section provides an overview of the groupings defined in the
"ietf-udp-server" module.

NEW:
This section provides an overview of the grouping defined in the
"ietf-udp-server" module.

• s/This example shows an example/The following shows an example
• s/Defines a generic grouping for UDP-based server applications/Defines a generic grouping for UDP-based servers