node utility can now display one/some/all key/values from node*/client.ini

<nelgin> Remind me why you can't show the ip address on node status? :)

Using the new '-v[key]' option, a sysop can view one, some, or all of the
key/value pairs from the nodes with a connected client. For nodes without
a connected client, the client.ini file values aren't particularly useful, but
if someone wants an option to show those values for non-client-connected nodes
I can do that too.

When using '-v', all the client.ini key/value pairs will be displayed for all
the node records requested with currently connected clients. By specifying
'-v[key]' the sysop can specify a key to display (rather than all of them)
e.g. 'node list -vaddr' to list nodes with remote client IP addresses.
This option can be used multiple times on the command-line to view multiple
keys. See node*/client.ini for the list of supported keys.

This feature only works for nodes whose directory paths are ../node#/
relative to the ctrl directory. Since the node utility doesn't read any
configuration files, this is a limitation. If you have different node
directory names/parents and need to use this feature, let me know and I'll
see about adding support for reading/parsing main.ini file to discover those
non-standard/default node directory paths automatically.

The version number displayed is now taken from the sbbs version (sbbsdefs.h).
The maximum ctrl directory path is now extended from 40 chars to MAX_PATH.
More readable help/usage output (using indentation).