Log Message:
math/kalk: update to 0.4.1

0.4.1
=====
-Use KalkNum's to_string() function in to_scientific_notation()
-kalk_web: Added integral and estimation support
-Combined to_scientific_notation() methods for both types, and added types,
and added tests
-Added wasm binding to KalkNum.estimate()

0.4.0
=====
-Fixed mod.rs errors for when rug is not used, and added some unit tests
-Estimation/rounding for final results
-Lex special symbols as one token
-Basic rounding for calculus functions
-Higher order derivatation
-Improved accuracy for derivation
-Basics of derivation
-Created 'Identifier' struct that contains prime count and name
-Fixed integrate function test
-Lex '**' as power sign
-Switched to Simpson's rule (composite, 3/8) for integration
-Fixed "dx" in integrals, and created calculus.rs
-Integration estimation
-Fixed zeroes being trimmed for non-rug numbers
-kalk: Fixed type error in kalk_num/regular.rs
-Trimming trailing zeroes for non-rug numbers
-Fixed xy^z precedence, from (xy)^2 to x(y^2)