Sprites improvements/cspect dropped

Please note:
Because of problems with cspect I had to drop support for it at the moment.
When the problems are solved I will put it in again.

Otherwise:

• Z80 unit tests fixed.
• Sprites/patterns view:
  • Grayscale palette exchanged by false colors palette.
  • Alternating colors for rows.
  • Visibility of anchor sprite is now taken into account.
• zrcp: Improved stability of socket connection.
• Disabled "cspect" support.

In order to install DeZog v1.2.6 in vscode use the command palette (F1) "Extensions: Install from VSIX..." and install the file below.