Improvements to maths, complex and hydroGOF keyboards in the calculator.

[Fidel365]

fixes issue #8878, @rdstern this is ready for review except for the following comment; The tooltip for the exp button in complex seems to be incomplete. Otherwise these changes are ready to be reviewd

[rdstern]

Maths keyboard: a) Good the packages are added to the maths keyboard and they all seem to work fine. Spell circular correctly. b) My mistake: correct for to from in maths > deg button c) atan key replace the double-dot (..) by just one. d) add tooltip for trunc tooltip: truncates the values towards 0. So trunc(3.5) = 3, trunc(-3.5)= -3

hydroGOF a) Well done. Just get rid of the comma at the end of mse.

complex in mod - it is 3*3 and 2*2 not 33 and 22. line up the key with congugat and add the e, so conjugate. If there is no space easily for this, then change to conj. delete the tooltip for exp for now. add tooltip for pi: pi = 3.14159 add tooltip for i i is defined as the square root of -1. So sqrt(as.complex(-1)) = 0 + 1i

[Fidel365]

@rdstern , this ir ready for a rereview.

[Fidel365]

@rdstern and @N-thony I have made the changes requested.