[pca] Recommended flag changes

[Martin Paul]

Craig Bell wrote:
> Gerry Haskins writes about upcoming refinements to the "Recommended"
> flag:

As stated in the article, Gerry Haskins and Don O'Malley have provided 
details about the planned changes to me beforehand. We've had some 
discussions in the last two weeks, and after working out the details I 
have now changed the current development release of PCA to cope with the 
future changes in the patchdiag.xref file and to retain current behaviour.

An official release will follow next week, to ensure that it's out 
before the first modifications appear in the patchdiag.xref file, as 
versions of PCA without the fix might not set the 'R' flag correctly on 
some patches.

Of course I plan to make use of the new information provided in the xref 
file as a next step. The ultimate goal would be to enable PCA to compare 
the current patch state of a machine to the new merged Recommended OS 
Cluster, to minimize the amount of patches to be installed to reach the 
Recommended patch state (ie. exactly the same as when applying the new 
Recommended OS cluster).

Unfortunately this might require rather massive changes to the code. As 
of now, PCA can only handle one revision per patch; all information 
stored about patches is in a central array indexed with the patch-ID. 
Adapting this to reference patchID-patchREVISION instead would mean a 
lot of changes, so I'll see if there's some other way for an implementation.

Martin.