new README

Author: mlubin

README.md

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-[preliminary documentation](http://jumpchance.readthedocs.org/)
+JuMPChance (formerly CCJuMP) is an extension to [JuMP](https://github.com/JuliaOpt/JuMP.jl) for formulating and solving optimization problems with chance constraints (also known as probabilistic constraints). JuMPChance currently supports only a particular class of chance constraints involving affine combinations of jointly normal random variables, a classical formulation that's known to be efficiently solvable by using second-order conic programming (SOCP) (although JuMPChance also provides an outer-approximation algorithm which solves a sequence of linear problems).
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+JuMPChance supports an extension of the classical model to distributionally robust (or ambiguous) chance constraints where the parameters of the normal distributions are known to fall in a symmetric interval or more general uncertainty set.
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+See the [documentation](http://jumpchance.readthedocs.org/) for installation installation instructions, a quick start guide, and a more detailed discussion of the methods implemented.