Improved early checking of prerequisite files

readme.org

@@ -1,5 +1,5 @@
 *** Current Version
-BerryPI 1.4.0 (May 25, 2018)
+Version 1.4.1 (Mar 08, 2019)
 *** [[https://github.com/spichardo/BerryPI/blob/master/licencing.txt][Licensing Conditions]]
 *** [[https://github.com/spichardo/BerryPI/releases][Download the whole package here]]
 *** [[https://github.com/spichardo/BerryPI/wiki][Documentation]]
@@ -13,7 +13,8 @@ BerryPI 1.4.0 (May 25, 2018)
 - [[https://github.com/spichardo/BerryPI/wiki/Tutorial-4:-Polarization-in-GaN][Tutorial 4 - Polarization in wurtzite GaN]]
 
 *** Limitation
-The present version is restricted to cases when the lattice vectors correspond to cartesian directions. For example, the zinc-blend or NaCl structures should be regarded as an 8 atom cell instead of the conventional 2 atom basis. This restriction is partly lifted (see - [[https://github.com/spichardo/BerryPI/wiki/Tutorial:-Non-orthogonal-lattice-vectors][Tutorial 3]])
+- Python 3.* is not supported
+- The present version is restricted to cases when the lattice vectors correspond to cartesian directions. For example, the zinc-blend or NaCl structures should be regarded as an 8 atom cell instead of the conventional 2 atom basis. This restriction is partly lifted (see - [[https://github.com/spichardo/BerryPI/wiki/Tutorial:-Non-orthogonal-lattice-vectors][Tutorial 3]])
 
 *** To Do
 - Non-orthogonal lattice vectors: Extending the capability of "BerryPI" to computing of polarization for structures with non-orthogonal lattice vectors