More detailed SET tests

Test both error triggering and behavior, including making sure that
no assignments are made when errors are supposed to be triggered,
and that multiple assignments are made or not properly.
Merge pull request #7 from BrianHawley/advanced-set-2

More detailed SET tests
Apply tests
Merge branch 'master' of https://github.com/rebolsource/rebol-test

Conflicts:
	core-tests.r
core-tests.r
- path constructions readded

log-diff.r
- debugging
-- problems with skipped tests
-- corrections of "log moving code"
- refining statistics
optimization, clarification
catch-any now RETURN/REDO -proof
DO-BLOCK wrapped into paren! now
comments enhanced
CATCH-ANY now properly classifies RETURN/REDO even when it causes errors, etc.
some exit, return and throw tests corrected (bug#1509)
Bug#1959: PARSE THRU properly positions to END
bug#75
bug#75 test is #r3only
Added a THROW test, a "dummy" HALT test (to not have an empty section), a couple of comments and ordered tests (some sections weren't contiquous)
the remaining tests ordered (forgot them at the end of the file)
bug#76
bug#77
* Date field removed from the header of all files (just a source of editing conflicts)
* interpreter checksum calculated from SYSTEM/BUILD if the interpreter executable isn't available to the test framework script
* Date fields removed from file headers (causing just editing conflicts)
* #*crash flags removed from core-tests.r
* #*crash flags removed from flags.r (flags aren't used from now on)
** the problem with flags was that they had to be readjusted manually after interpreter changes
date field removed from the header of the log-diff.r file