Hopac 0.1.1

XML documentation was missing from `0.1.0`. Updated `FSharp.Core` dependency to `4.0.0.1`. Redesigned infix operator symbols to allow most common expressions to be written without parentheses and also added several new infix operators. See the documentation for details. Moved all infix operators to the `Hopac.Infixes` module so that one only has to open one module to use infix operators. Introduced `Alt.prepare*` and `Alt.after*` combinators for clarity and uniformity to replace `delay`, `guard` and `wrap`. Added `Job.isolate` as a workaround for scheduling issues. Minor additions: `Seq.foldFromJob`, `Proc.bind`, `Proc.map`.