make selection a bit less bold.
fix broken test.
when the editor selection crosses a blank line, show half an em-width of selection, so it's clear that the selection includes the blank line.
bad.
add support for HLT (don't bother running until an interrupt arrives), step-over, and switching tabs with alt-tab, alt-shift-tab.
dim the cursor highlight line a bit.
fix "over" to be ok with both sides of a branch.
tab now goes to the editor.
fix bug with blinking.