documentation overhaul (#353)

* ident
* remove $Id$ tags from rcs software which has been retired
* make an effort to sync required mib docs with actual code
* sync even more docs with what code actually does
* some whitespace nits
* fixup example to use snmpv2 for all but the most ancient devices
* remove blurb to find more specific snmp::info classes for classes
  which alrdy are as specific as they can get (eg snmp::info::layer3::vmware
  doesn't need info on to find a specific module since there ain't none)
* rename all sub {vendor} strings to lowercase vendor, if cisco, juniper
  and arista can be lowercase, so can be all the rest.
* fix tests
* spread some use warnings around
* use $ instead of @
* remove defines that are included via parent classes
* use strict + warnings
* remove alrdy included modules
* add comma after last list item
* typos
* mibs are found in our mib repo, not on the cisco site
* documentation fixes

lib/SNMP/Info/Layer3/Timetra.pm

@@ -1,5 +1,4 @@
 # SNMP::Info::Layer3::Timetra
-# $Id$
 #
 # Copyright (c) 2008 Bill Fenner
 #
@@ -30,7 +29,7 @@
 package SNMP::Info::Layer3::Timetra;
 
 use strict;
-
+use warnings;
 use Exporter;
 use SNMP::Info::Layer3;
 use SNMP::Info::Aggregate;
@@ -120,7 +119,7 @@ sub model {
 
     my $str;
 
-    if ( $descr =~ /\s+(7\d{3})/ ) {
+    if ( defined ($descr) && $descr =~ /\s+(7\d{3})/ ) {
         $str = $1;
     }
 
@@ -146,7 +145,7 @@ sub os_ver {
     my $timetra = shift;
 
     my $descr = $timetra->description();
-    if ( $descr =~ m/^TiMOS-(\S+)/x ) {
+    if ( defined ($descr) && $descr =~ m/^TiMOS-(\S+)/x ) {
         return $1;
     }
     return;
@@ -454,7 +453,7 @@ These are methods that return scalar value from SNMP
 
 =item $alu->vendor()
 
-Returns 'alcatel-lucent'
+Returns 'nokia'
 
 =item $alu->os()