qrcm 3.0

Changes with respect to version 2.2

• bug with survival 2.41 fixed in a better way (timefix = FALSE).
• added new function: iqrL and associated auxiliary functions
• renamed internal functions
• defined a test.fit method. Allow R = 0.
• improved starting points, better estimation of Jacobian and outer product
• handling of potentially discrete data in start.iqr and trans
• fixed warnings with PDF < 0, and wrong definition of covar.ok
• fixed predict (contrasts)
• fixed plf with scalar input
• new dependency pch >= 2.0
• functions for quantile crossing
• added obj.function for censored and truncated data