Support 'older than' when inventory filtering

Open the inventory floater Click on the gear button: you see a menu entry Show Filters... (note "..." is new and part of this change) Click on Show Filters... Input 36 into the Hours field. Test 3 ways using enter/return, tab, and shift tab: the hours field changes to 12, the days field changes to 1, and the hours field remains selected/highlighted. Test using a larger value and making sure that the displayed results are newer than the datetime inputted. Test using the up hour spinner control: when hours goes up from 23: hours is reset to 0 and 1 is added to the current day value. Click the increment hours spinner many times again to have it roll over for a second time from 23 to 0: days increments again by 1. Click on the Older than radio button and verify that results match expectations. Click on the Recent tab and perform the above tests Log off Log on Open the inventory floater Open the Filters floater Click on the recent tab: the values that you had set just before logging off have been preserved across the log off/log on sequence. Perform this off/on test again, selecting the other radio button this time. Notes: To reset the hours and days fields to 0 check and uncheck Since Logoff Some folders open automatically to show the results of filtering; others you have to open manually.