Issue 110 - Dividing message text into sms's between words

I made changes to a file "src/esmska/data/Envelope.java". I added a method to find the index of cut and method to cut message text into sms's and add sms's to the list.
Method findIndexOfCut - Finding a place(index) where messages are separated. Attempts to separate the messages between words. If can not find white space to 20% length of message text from the original cut place, cut the word.
Method cutOutMessages - uses method "findIndexOfCut", passes through text of message and divides it into sms's, which adds to the list.This method is called in the method "generate()".