Minor FITS edits

1) Violation in Value range or Comment part

- DATA-TYP : value 'ARC' is not registered in Subaru FITS rule
- DET-TMP  : unit should be [K] -> needs to fix on the dictionary side?
- ADC-TYP  : Comment 'ADC name' is wrong for the present example 'IN'
             Dictionary requests name of ADC rather than state (such as 'IN')
             but this may need further discussion on the dictionary side (ex. HSC also shows state 'LINK' for this card)
- EXPTIME  : Unit is missing

2) Unregistered keyword (to be registered in Subaru basic keyword dictionary)
- DARKTIME : Unit is also missing

4) Unnecessary keyword that may be better to be removed
- M2-TYPE : existence of M2 may be confusing

5) Wrong keyword name
- ADC-TYP --> ADC-TYPE
- FOC_VAL --> VOC-VAL

8) Others/Misc
- DET-ID : recommended for STARS
- BLANK/ZBLANK :  Subaru rule also needs to define where to put BLANK keyword in the MEF case
                and presumably should require ZBLANK in compressed data