Improve the list of "Standard numerical functions" offered on the math dialog by including more standard functions.

The current list is: [proposed removals ~~struck out~~]

exp, exp_a, ln, lg, log, log_10,

sin, cos, tan, sec, csc, cot, arcsin, arccos, arctan, arcsec, arccsc, arccot

sinh, cosh, tanh, coth, ~~sh~~, ~~ch~~, ~~th~~, ~~argsh~~, ~~argch~~, ~~argth~~

~~sgn~~, ~~|s|~~, ~~min(x, y)~~, ~~max(x, y)~~

(https://en.wikipedia.org/wiki/Help:Displaying_a_formula#Standard_numerical_functions)

A suggested list is: [new ones **in bold**]

exp, log, lg, ln, log10, **arg**, **Lis**

sin, cos, tan, sec, csc, cot, arcsin, arccos, arctan, arcsec, arccsc, arccot

sinh, cosh, tanh, **sech**, **csch**, coth, **arsinh**, **arcosh**, **artanh**, **arsech**, **arcsch**, **artanh**

**erf**, **erfc**, **logit**

**Re**, **Im**

(https://en.wikipedia.org/wiki/Wikipedia:VisualEditor/Feedback/Archive_2015_3#Expanded_formula_tool_in_VisualEditor)

How about making the new list the union of these two lists?