fix memory leak

checkPortRole: do not store every object's links, only the last one's
list plugins/* in .gitignore
suppress some table rows in renderLocationPage()

Suppress atributes that are empty or not allowed by RackCode
permissions. This brings the function into line with similar code.
overridable ssh gateway command-line options

gateways/ssh: removed all options except of --as-user. Added ssh options pass-through
makeGatewayParams: new hook. Code from queryTerminal moved here
queryTerminal: call makeGatewayParams hook to translate settings info CLI options
bulk port creation failed with empty prefix

addBulkPorts: made string assertion aware of empty string
RS pool cloner was throwing an exception

cloneRSPool: fixed variable name erro
detectDeviceBreed for Cisco IOS 12 routers
LLDP support for Juniper devices

jun10ReadLLDPStatus: new parser func
jun10TranslatePushQueue: opcode translation added
new hook alterDeviceQueryResult

This is to allow changing the result of queryDevice before it returns.
For example, you could make some additional remote queries to extend or
fix data returned by standard query handler.

queryDevice: replace $ret, if user intends to
registerHook: fix exception when chaining non-existant function
support IOS XR4 interface names

ios12ShortenIfName: IOS XR4 regexps added
ASR 9000 LLDP support

iosxr4ReadLLDPStatus: new LLDP parser for IOS XR4
ios12ShortenIfName: support 'BE' IOS XR acronym
renderIPForObject: removed PHP notice (#759)

use array_last instead of array_pop
address some rack deletion issues (#757)

This is likely to fix future removals of racks, but does not address
files and tags that could be left over past removals (FK exists between
Rack/Object and RackSpace tables only in this context).

* commitDeleteRack(): remove unused function, anyway it is broken since
  RackHistory table was dismissed
* deleteRack(): handle removal of associated data (files, tags and
  non-object rackspace)
assign IP addresses to objects whose type is Wireless (#755)
deleteLocation(): references to tags and files remained when a location
was deleted (#747)
renderRackspaceLocationEditor: resolve strict PHP warning
add SNMP support for Linksys SRW224G4 (#743)
also change the port label for some Dell switches
allow files to be linked to rows (#733)
amend previous commit (update install.php as well)
SNMP: add support for 3Com 4210 52-port (#763)