Plus42 algebraic expressions update

[Vincent Weber]

Thanks Thomas, progressing well, and general comparisons are a nice addition too !
Maybe something should be done to access the parenthesis. On the 27S/17BII you have dedicated keys, but not on the 42S, so you have to dig several layers of alpha menu to find them - not so practical when you just want to close SIN(X !
I'm sure you'll also find a way to put INTEG in equations

Cheers