0.27

The 0.27 release is focused on improving the float shrinking support and also contains a small patch to make the package compile with OxCaml:

• Add QCheck.Shrink.float and enable shrinking for QCheck.float
• Add QCheck.Shrink.float_bound and enable shrinking for QCheck.float_bound_inclusive and QCheck.float_bound_exclusive
• Add QCheck.Shrink.float_range and enable shrinking for QCheck.float_range
• Enable shrinking for QCheck.{pos_float,neg_float,exponential}
• Patch QCheck.Print.float and QCheck2.Print.float to print negative nans consistently as "-nan" also on Windows and macOS, and correct documentation for QCheck.{float,pos_float,neg_float} in that they may produce nans since #350 from 0.26
• Eta-expand a couple of partial application to compile under OxCaml