implement special math functions

[mattkretz]

• [x] sin
• [ ] cos
• [ ] sincos
• [ ] tan
• [ ] asin
• [ ] acos
• [ ] atan
• [ ] atan2
• [ ] asinh
• [ ] acosh
• [ ] atanh
• [ ] sinh
• [ ] cosh
• [ ] tanh
• [ ] exp
• [ ] exp2
• [ ] expm1
• [x] frexp
• [ ] ilogb
• [ ] ldexp
• [ ] log
• [ ] log10
• [ ] log1p
• [ ] log2
• [x] logb
• [ ] modf
• [ ] scalbn
• [ ] scalbln
• [ ] cbrt
• [x] abs
• [ ] hypot
• [ ] pow
• [x] sqrt
• [ ] erf
• [ ] erfc
• [ ] lgamma
• [ ] tgamma
• [x] ceil
• [x] floor
• [ ] nearbyint
• [ ] rint
• [ ] lrint
• [ ] llrint
• [ ] round
• [ ] lround
• [ ] llround
• [x] trunc
• [ ] fmod
• [ ] remainder
• [ ] remquo
• [ ] copysign
• [ ] nan
• [ ] nextafter
• [ ] nexttoward
• [ ] fdim
• [ ] fmax
• [ ] fmin
• [ ] fma
• [x] fpclassify
• [x] isfinite
• [x] isinf
• [x] isnan
• [x] isnormal
• [x] signbit
• [ ] isgreater
• [ ] isgreaterequal
• [ ] isless
• [ ] islessequal
• [ ] islessgreater
• [x] isunordered
• [ ] div

[ArifAhmed1995]

tgamma implementation would be important for vectorization of TMath library of ROOT. There are quite a few functions which use it.