[isabelle-dev] Towards the Isabelle2015 release

[Makarius]

If all goes well, there will be Isabelle2015-RC1 today in the evening. 
Until then there is still the opportunity to update NEWS and CONTRIBUTORS,
which are also relevant for the website.

The publication of Isabelle2015-RC1 does not yet mean a fork of the 
repository yet: there will be a few more days to sort out reported 
problems directly in the main Isabelle repository.


 	Makarius