add new math functions
Merge https://github.com/DavePearce/Whiley
Merge pull request #256 from beenshi/master

new math functions: sin, cos, tan, asin, acos, atan, exp, log: via java native functions
Merge branch 'master' of github.com:DavePearce/Whiley into devel
Merge branch 'devel' of github.com:DavePearce/Whiley into devel
Change to rule for inequalities.