Refactorings and compatibility fix

This pull request includes some refactorings in the front end together with the fix for issue #40 (closed). Moreover a few fixes have been added to fix the issue #41 (closed). These fixes include:

• cb are also printed on the first page.
• Changing location of cb doesn't put them horizontal.
• Cb align with placeholder image.
• Cb do not have their y-axis inverted.
• Corrections to documentation.