separated key functions

Moved all variables that were styles and functions that reset
these variables or returned new variables into the style.go file.
Functions that actually do something interesting are now in functions.go
Added StyleWriter function

First, I apparently forgot to commit this file when
moving variables to styles.go.

This commit adds the StyleWriter function that can
be used with fmt.Fprintf to always print a saved style.
See last commit...
removed SaveStyle and SavedStylize functions

These are made useless by StyleWriter and also are too
verbose for practical use.
change %v to %s to print interpreted byte slice
remove sgr from lineEnd, unneeded, oops