shodanhq does not have update_hosts

Quick fix for shodanhq process_report which doesn't have update_hosts boolean.
Adds get_or_create_record to skaldship.hosts

New function, get_or_create_record, for routines that want to return a t_hosts
record from an IP address or t_hosts.id. If IP provided but does not exist
get_or_create_record will create a new record with the list of arguments
added after validation against t_hosts.fields.

Default for f_asset_group = undefined
Default for f_engineer = 1 (only used when no session)
Merge pull request #108 from grutz/get_or_create_host

Adds get_or_create_record to skaldship.hosts
Large revamp of host filtering

* The filter content is now passed as a JSON string between web2py and the ui.
* Clear Filter does what you think it should now
* Fix pagination when filtering on an Engineer
* Added booleans for accessed and follow up
* Fixed a number of additional bugs
* Removed address range since it may never be implemented
* Additional little tweaks to UI
Merge pull request #109 from grutz/filter_fix

Large revamp of host filtering