enable loading subset of all nodes

potential use in perhaps upcoming CLI:

[fisakytt@lan-login1 ~/projects/oxidized-cli]% ./oxi S-2250219.fi.cpe.tdc.net 'show ver'
                Dec  2 2009 00:19:01
                Q.11.25
                106
[fisakytt@lan-login1 ~/projects/oxidized-cli]% ./oxi 62.236.123.197 'show ver'
Cisco IOS Software, C3560 Software (C3560-IPBASEK9-M), Version 12.2(55)SE1, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Thu 02-Dec-10 07:16 by prod_rel_team
Image text-base: 0x01000000, data-base: 0x02D00000

ROM: Bootstrap program is C3560 boot loader
BOOTLDR: C3560 Boot Loader (C3560-HBOOT-M) Version 12.2(35r)SE2, RELEASE SOFTWARE (fc1)

S-1035880.fi uptime is 7 weeks, 3 days, 15 hours, 43 minutes
System returned to ROM by power-on
System restarted at 00:54:59 UTC Wed Feb 19 2014
System image file is "flash:c3560-ipbasek9-mz.122-55.SE1.bin"

This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html

If you require further assistance please contact us by sending email to
export@cisco.com.

cisco WS-C3560-8PC (PowerPC405) processor (revision F0) with 131072K bytes of memory.
Processor board ID FOC1449W2ZU
Last reset from power-on
2 Virtual Ethernet interfaces
8 FastEthernet interfaces
1 Gigabit Ethernet interface
The password-recovery mechanism is enabled.

512K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address       : 10:8C:CF:F0:68:80
Motherboard assembly number     : 73-10612-09
Power supply part number        : 341-0207-02
Motherboard serial number       : FOC14493DDW
Power supply serial number      : LIT14430ZXA
Model revision number           : F0
Motherboard revision number     : A0
Model number                    : WS-C3560-8PC-S
System serial number            : FOC1449W2ZU
Top Assembly Part Number        : 800-28131-04
Top Assembly Revision Number    : C0
Version ID                      : V04
CLEI Code Number                : COML900ARA
Hardware Board Revision Number  : 0x01

Switch Ports Model              SW Version            SW Image
------ ----- -----              ----------            ----------
*    1 9     WS-C3560-8PC       12.2(55)SE1           C3560-IPBASEK9-M

Configuration register is 0xF
[fisakytt@lan-login1 ~/projects/oxidized-cli]% cat oxi

require 'pry'
require 'pp'
require 'oxidized'
require 'resolv'
module Oxidized
 class Oxi

   def cmd command
     @model.cmd command
   end

   def disconnect
     @input.disconnect_cli
   end
   alias_method :close, :disconnect

   private

   def initialize node
     Oxidized.mgr = Manager.new
     @node  = Nodes.new(:node=>node).first
     @model = @node.model
     @input = nil
     connect
     if block_given?
       yield self
       disconnect
     end
   end

   def connect
     @node.input.each do |input|
       begin
         @node.model.input = input.new
         @node.model.input.connect @node
         break
       rescue
       end
     end
     @input = @node.model.input
     @input.connect_cli
   end

 end
end

Oxidized::Oxi.new(ARGV[0]) do |cli|
  puts cli.cmd ARGV[1]
end
[fisakytt@lan-login1 ~/projects/oxidized-cli]% ls -la
total 12
drwxrwxr-x 2 fisakytt fisakytt 4096 Apr 12 19:39 .
drwxrwxr-x 7 fisakytt fisakytt 4096 Apr 12 17:52 ..
-rwxr-xr-x 1 fisakytt fisakytt  820 Apr 12 19:39 oxi