1.3    26-05-2024: Version 3.4 of the Isabelle ITL proof library
      
- Deep embedding of PITL and QPITL is included to allow for proofs of theorems about them,
notably that any PITL or QPITL formula can be rewritten in Guarded Normal Form (GNF)
[2, 34].
- Added definition and lemmas for the time reversal operator, ported from the ITL v2.x series.
Note only finite ITL formula can be reversed.
- The  document  structure  is  now  report  with  four  chapters:  1  Model:  Intervals;  2  Shallow
embedding of Finite and Infinite ITL; 3 Deep embedding of PITL; 4 Deep embedding of QPITL.