mathlib

[Roberto Ierusalimschy <roberto@...>]

We are considering removing some functions from the standard math lib,
either because we think few people use them or because they are trivially
implemented without the library. The current list is this:

- sinh, cosh, tanh: (They are quite specialized, on par with several
other functions offered by external libraries, such as lhf's mathlibx.)

- deg, rad, pow: trivially done without the library.

Comments?

-- Roberto