phpstan fix, tcltk distribution build script

• a warning from phpstan has been fixed
• Makefile for building Tcl/Tk distribution has been added (tested on Windows)

Fix installing dependencies on php8.2

• Fix installing dependencies on php8.2
• Fix phpstan errors regarding to FFI\CData::cdata property which is dynamic one

Fix reading env

This release fixes reading environment variables passed through command line.

Progressbar widget, app icons

Release highlights:

• progressbar widget and demo
• Tcl core list variables
• Allowing to set the application icon
• Allowing to set the application name

Fix documentation

• Added dependencies install command in Installation section.
• treeview demo renamed as it shows only list view capabilitites.

Fix PHP7.4 compatibility

Merge pull request #11 from skoro/fix-php74-errors

Fix php74 errors

Initial release

v0.1.0

fix header env vars and disable them by default