Add styling for exisitng Elements

• Update starting window size and min sizes for sidebar and note editor
• Left sidebar file styling alone b/c it will be refactored and completely changed into the tree view
• add Lato font for note title in sidebar
• add png icon files

NOTE: Need to someone to confirm there is nothing crazy going on Windows

NOTE: If the font fails to load and errors out it might be because you have a space in your file path to the project, this is a bug in javafx source