added comments of where the code for computehighlighting was taken from

https://github.com/TomasMikula/RichTextFX/blob/master/richtextfx-demos/src/main/java/org/fxmisc/richtext/demo/JavaKeywords.java
trying out other colour schemes

http://www.colourlovers.com/palette/1930/cheer_up_emo_kid
changed border widths