Release icewm-2.9.9

Permit percentages to have a decimal point in the icesh commands "sizeto" and "sizeby".
Improve the updating of workspace buttons for PagerShowPreview.
On window changes, only redraw affected workspace buttons, which reduces the total
number of workspace button redraws, especially for large number of workspace buttons.
Add new key bindings for single window tiling operations for issues
bbidulock/icewm#335, #74 and #84.
Support more HTML entities in icehelp.
Remove dependency on asciidoc and prefer markdown format for the manual.
Automatically detect and prevent race conditions in icesh
relating to moving and sizing windows for issue bbidulock/icewm#335.
Improve the accuracy of the "sizeto" command in icesh for issue bbidulock/icewm#335.
Add new "extents" and "workarea" commands to icesh.

shasum icewm-2.9.9.tar.lz fb0a9b5fe5b4748d509880c6c6d88fda0a477662