ra time range option

[Clauss Strauch]

Hello,
	Here are some ideas on specifying time ranges for ra.  I don't know
how tough they'd be to implement, but 'pick' (the MH command) does something 
similar.

						-- Clauss

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a given time t partitions flows into 3 sets:

flows that overlap that time.

flows that end before t

flows that start after t

two time vals, t1 < t2, partition flows into 6 sets (Fn is an example flow
for each set):

      F1 |======| 				 F2 |=========|
           F3 |================|
                                           F4 |=========|
              F5 |===========================================|

                      F6 |=====================|
     |-------------|-----------------------------|-----------------|
		  t1				t2


F1: flows that end before t1
F2: flows that start after t2 
F3: flows that overlap t1 but not t2 
F4: flows that overlap t2 but not t1 
F5: flows that overlap both  t1 and t2
F6: flows that begin and end in the t1..t2 interval

Also, we're interested in a another set: 
F7: the current time interval matching returns the union of F3 & F4 & F6

we want to be able to specify any of these sets without being too convoluted
wrt argument syntax.

Use 3 time selection switches:

-before t
-after t
-during t[-t]
-and 

-before t1      = selects all flows ending before t1
-after t2       = selects all flows starting after t2
-during t       = selects all flows overlapping t
-during t1-t2   = selects all flows overlapping any  t1 =< t =< t2
-and 		= union

F1: flows that end before t1                     = -before t1
F2: flows that start after t2                    = -after t2
F3: flows that overlap t1 but not t2             = -during t1 -and -before t2
F4: flows that overlap t2 but not t1             = -during t2 - and -after t1
F5: flows that overlap both                      = -during t1 -and -during t2
F6: flows that begin/end in the t1..t2 interval  = -after t1 -and -before t2
F7: the current time interval syntax		 = -during t1-t2