RFR: JDK-8027566 Remove the old build system

[Magnus Ihse Bursie]

Bug: https://bugs.openjdk.java.net/browse/JDK-8027566

This is the aggregation of the three previous preliminary reviews posted.

Since there previous webrevs did not result in any suggestions of code 
changes, the actual code is basically the same here as in the three 
preliminary, with two exceptions.

First, the addition of a new version of the compare script 
(common/bin/compare.sh) which was needed to properly compare the build 
results with the previous output. (Prior to that fix, the compare script 
assumed you were comparing with the build bits from the old build system.)

Second, I fixed an issue with bootcycle-images, which I didn't detect 
earlier.

Also, with the broken webrev script fixed, it is easier to spot if a 
file was just moved, or if it also was modified. (This was not clear 
from the early partial reviews.)

We have verified, using the compare script, that the resulting build 
bits do not differ from what was build before this patch was applied. 
This comparison is still not finished for a few platforms, but we have 
tested the majority and found no regressions. We will continue testing 
the last platforms, but we don't expect any surprises.

WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8027566-remove-old-build-system/webrev.01

For reference, here are the three previous webrevs, were the separate 
steps in the removal process can be traced:

Part 1: Removes (conservatively) the majority of the old build, and 
replaces the top-level Makefile.
http://cr.openjdk.java.net/~ihse/remove-old-build-part-1/webrev.02/

Part 2: Prepares make/* and makefiles/* for merging, and removes the 
last bits of the old build system.
http://cr.openjdk.java.net/~ihse/remove-old-build-part-2/webrev.02/

Part 3: Moves the files in makefiles/* to make/*.
http://cr.openjdk.java.net/~ihse/remove-old-build-part-3/webrev.06/

/Magnus