remove cap for F (this causes violations of the C^1 property in certain cases)
require decreasing call prices for exponential extrapolation
fix floor pricing
fix error check in vanilla engine tests,
exclude 0.10 strike and change strike 0.07 to 0.06 in cap engine test,
use correct yield and volatility termstructure in cap engine test
Merge pull request #26 from Peter Caspers.

Fixes for Markov-functional cap-floor engine and Kahale smile section.