PNG decoder computes Adler32 checksum for Deflated data, as expected
(gwindows) TeXCAD runs as single instance (mechanism from LEA/AZip); zoom info updated on subwindow switch
Eliminated some name hidings (switch: -gnatwh)
(gwindows) Shortened some identifiers
(gwindows) Added tabs bar (adapted from AZip/LEA)
Source code cleanup (-gnatwh)
Improved documentation
Added text representation decoding and I/O consistency tests