[Release] Organising Fixes

[Keith Hodges]

Instead of having fixes organised in both classes

ReleaseAfterSqueak310
 and
ReleaseAfterSqueak310Unstable.

we now have one organization of fixes in ReleaseAfterSqueak310, but each
fix can be flagged...

#fix:  installs the fix.
#fixIfUnstable: installs the fix, but only in an unstable image.
#fixOneDay: does not install the fix, it is a placeholder to be enabled
in the future.

e.g.

fixesKernelStreams
   
    ^ self dependingOn: {
   
         self fixOneDay: '0007167: ReadWriteStream opened with on:
aCollection always has readLimit 0'.
     
    }

cheers

Keith