Version 0.7.5

It has been a while since the last release.  This release includes:

Kees van Oss released a compiler, engine and build suite for the BBC Model B.

Moving or resizing the play area retains screen data and sprite positions are modified accordingly.

Sprites can be grabbed from a scratchpad screen, which can be imported from a 6K Acorn/Dragon or 6.75K Spectrum screen display.

Screens can now be scrolled around with the cursors in the editors.

The MSX has been added as an option.  The compiler and engine are not yet ready but can be slotted in easily once released.

Blocks can be inverted.

Check game tool improved.

The ZX Spectrum now has a debugger option for 128K machines.

Spectrum, CPC and Timex compilers now have an option to build with or without AY sound

A few bugs fixed.

Documentation updated.