Wilders Smoothing

``` use tacommon::traits::Indicator; use wildersrs::Wilders;

let mut wilders = Wilders::new(5); asserteq!(wilders.next(81.59), None); asserteq!(wilders.next(81.06), None); asserteq!(wilders.next(82.87), None); asserteq!(wilders.next(83.00), None); asserteq!(wilders.next(83.61), Some(82.6628)); asserteq!(wilders.next(83.15), Some(82.76024)); asserteq!(wilders.next(82.84), Some(82.776192)); asserteq!(wilders.next(83.99), Some(83.0189536)); asserteq!(wilders.next(84.55), Some(83.32516288000001)); asserteq!(wilders.next(84.36), Some(83.532130304)); asserteq!(wilders.next(85.53), Some(83.93170424320002)); asserteq!(wilders.next(86.54), Some(84.45336339456001)); asserteq!(wilders.next(86.89), Some(84.940690715648)); asserteq!(wilders.next(87.77), Some(85.5065525725184)); assert_eq!(wilders.next(87.29), Some(85.86324205801472)); ```