Instances of different runs for target and best

Every attempt was made to make the best area cover the same area as the target area, and to make the chunk boundaries the same. For the most part the target and best start and endMu's for the same chunk of sky agree to within 1'', however there are a few exceptions which we list below:

Stripe 82:

Target skyVersion goes from startMu = 1176576 to endMu = 1499432 (the unit here of startMu and endMu are int(arcseconds), and it can go beyond 360*3600 to avoid endMu < startMu).

Best skyVersion goes from startMu = 1243586 (18 degrees later) to endMu = 1510917 (3 degrees later)

These don't match because:

1. we replace runs 1033/1056/94/125 with runs 2662,2738 and 3325 (somewhat better data), and 3325,2738 go a bit beyond 94/125, but 2662,3325 don't go all the way to the beginning of 1033,1056.

2. we needed to avoid the 'astrometrically offset by 74 arcsec' run 1056 and thus avoid 'gaps' in the filled best skyVersion of the stripe 82 between scanline (camCols) at the beginning of the run. This run 1056 exists in the 'resolved' target skyVersion, and we can't remove it from the target imaging data (or we lose that information), however, the plate which covered runs 1056 have been removed from DR1 to avoid having to explain the gaps in the imaging coverage. We will probably get questions on the gaps in the imaging coverage anyway if people look at the imaging from target only, but we'll deal with that as we need to.

3. There wasn't a substitute for run 1056 available at the time the best skyVersion was constructed which covered this area.

Large scale structure folks should note that the plates which covered runs 1056 have been removed from DR1, as this is relevant for the tiling masks, even though the tiBoundaries file for this tilingRun will have the area of some of these plates in it.

Other small (<1 field) differences at the ends of stripes are:

stripe 37, startmu 788748: endMu(target)= 839942 endMu(best)=840481 (best extends 1 more field due to roundoff, doesn't affect any plates).

stripe 9, startMu 614999/615000: Astrometric roundoff (different version of astrom run target vs. best, results in <<1'' roundoff in startMu for this chunk.

stripe 11, startMu 546385: endMu(target)=822557, endMu(best)=822553 roundoff difference of endmu for last field (4'')

stripe 12, startMu 604610: endMu(target)=666827, endMu(best)=667366 (best extends 1 more field due to roundoff, doesn't affect any plates).