Few misprints

Dear Matthias Vallentin!
Your cookbook is great and almost exhaustive.
But could you please re-check the following in the 4 Expectation section:

1. The formula EX=sum(P{X>=x}) is right only for integer-valued RVs. Probably it should be mentioned explicitly.
2. The last formula in Conditional expectation probably needs another parentheses configuration.

[mavam]

Thanks for the report, I've incorporated your suggestions and just released version 0.2.3.