[Bug-apl] Format by specification - bug in exponential display

[apm]

I get the following when using ⍕:

      12 ¯4 ⍕ 9.9994 9.9995 9.9996 ¯9.9995E¯10 ¯9.9996E¯10
     9.999E0     9.999E0     0.000E0  ¯0.000E¯10  ¯0.000E¯10

This should display as:
     9.999E0     1.000E1     1.000E1   ¯1.000E¯9   ¯1.000E¯9

The error in  (12 ¯4 ⍕ 9.9996 ¯9.9995E¯10 ¯9.9996E¯10) seems to be 
related to the failure to increase the exponent by 1 and reduce the 
coefficient by 9 when the coefficient rounds to 10.000

The error in (12 ¯4 ⍕ 9.9995) is probably related to ⎕CT and 
binary/decimal conversions and may not be considered a true error.