How to build the project + Fixed BL behavior + Fixed SUBS Flags Setting Behaviour

[simdeistud]

This pull request contains the following 3 items:

1. A fix for the incorrect implementation of the BL instruction
2. A fix for the incorrect implementation of setting the flags in a SUBS implementation, which in turns fixes the CMP instruction and finally allows for correct branching.
3. A folder containing a tutorial on how to set up the Java environement to build this project. The tutorial will also be uploaded below as a pdf or as a continuous web page.
   How to set up Eclipse to develop the LEGv8 simulator.pdf
   How to set up Eclipse to develop the LEGv8 simulator.zip
   If you want to contribute to the project you should add the AceGWT folders imported to Eclipse to the .gitignore file in order to not upload them to this repository when you do your commits.

P.S.
You must use an Eclipse version no newer than 2023-09 otherwise the GWT plugin cannot be installed.

This effort has been made in the context of the Digital Systems Architectures course held at the Department of Engineering and Architecture at the University of Trieste under the guidance of Prof. Alberto Carini .