spare IPv6 prefixes are limited to nibble boundary

splitNetworkByMask: new library function
iptree_fill: use net's pre-calculated ['spare_ranges'] array
iptree_construct: removed
iptree_embed: removed
button to fix non-canonical port names (#827)

	shortenPortName: a caching wrapper around detectDeviceBreed and shortenIfName
	renderObjectPortRow: highlight port name with yellow if it's name is not canonical
	renderPortsForObject: idem, display rename link
	renameObjectPorts: new ophandler
bugfix: include Zero-U into ['mountedObjects']

amplifyCell: Zero-U-mounted objects were not counted in rack summary
display rack power consumption (#701)

	populateRackPower: function that alters $summary
	renderRackInfoPortlet: call populateRackPower()
Fix for http://bugs.racktables.org/view.php?id=837

Bug #837 describes wrong sort-order for objects with polish characters. This should be fixed by using "collate utf8_unicode_ci" on all tables explicitly.
isInnoDBSupported: fix failed upgrade reentrance

If the upgrade script failes on creating a trigger
because of binary logging is turned on, it keeps the innodb_test table,
preventing further calls of isInnoDBSupported().
new dictionary item Cisco 2960X*