create text matrix

takes a string, returns a matrix of 1s and 0s. text string is 'painted' by 1s on a background of 0s

sometimes, you want an image that contains text, instead of manually drawing 1s and 0s , this functino takes a string and returns a matrix of 1s and 0s in the form of that string. (tjhe matrix is rectangular the text string is represented as being painted by 1s)