REGRESSIONS update for past week or so

This is about a week's worth of regressions updates.  As usual, some things have come and gone and can be seen in individual commits.  The only real issue of concern here is the cce-as-host-compiler issue (first new regression below) which Mike is going to look into as the 2/3 likely owner.  Most of the diffs in the file are due to continuing to shake out the new REGRESSIONS format w.r.t. the new naming schemes and xe testing still coming back for the first time under the new names.

New regressions
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* compiler failures when cce used as host compiler -- mike taking a look
* record_from_string future .bad mismatch everywhere (now fixed by hilde, still trickling through system)
* new memleaks timeouts due to moving testing to chap16
* new sporadic timeouts in gasnet.linux32

Fixed issues
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* test_block2d_2 has been resolved on gasnet-everything for some time now -- removed

Misc
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* added playground perf categories based on new naming scheme\
* moved sporadic failures to ends of their categories
* improved xe-/xc- whitebox categories and inheritance, particularly as XE testing has started to come in