Several subroutines added

list-slice - slicing list between two indicies
list-insert-at - insert element in position in list
string-contains - check if string contains substring
userinput-prompt-default - generate prompt string and get value with default option
math-degrees-radians - convert degrees to radians
math-radians-degrees - convert radians to degrees
reactor-set-on-command - set reactor on commands list to execute provided subroutine before and after command