Replacing the call to SIMPLIFY() in CHEBFUN/QR()

This was earlier removed because of problems with both EPSLEVELS and CHEBFUN2/PLUS. These have no stabilised sufficiently that only two trivial tolerance changes were required for all the tests to pass.
Tweak tolerance.
Merge remote-tracking branch 'upstream/development' into fix-chebfun-qr
Tweaking tests.
Merge pull request #980 from chebfun/fix-chebfun-qr

Replacing the call to SIMPLIFY() in CHEBFUN/QR()