REQUIRED NUMERIC CAPABILITIES
	:co#:	number of columns on the screen (characters per line)
	:li#:	number of lines on the screen

REQUIRED STRING CAPABILITIES
	:ce=:	clear to end-of-line
	:cl=:	home the cursor & clear the screen
	:cm=:	move the cursor to a given row/column
	:up=:	move the cursor up one line
	:ic=:	insert a blank character

BOOLEAN CAPABILITIES
	:am:	auto margins - wrap when a char is written to the last column?
	:pt:	physical tabs?

OPTIONAL STRING CAPABILITIES
	:al=:	insert a blank row on the screen
	:dl=:	delete a row from the screen
	:cd=:	clear to end of display
	:ei=:	end insert mode
	:im=:	start insert mode
	:dc=:	delete a character
	:kd=:	sequence sent by the down arrow key
	:kl=:	sequence sent by the left arrow key
	:kr=:	sequence sent by the right arrow key
	:ku=:	sequence sent by the up arrow key
	:sr=:	scroll reverse (insert a row at the top of the screen)
	:vb=:	visible bell

OPTIONAL CAPABILITIES THAT DESCRIBE CHARACTER ATTRIBUTES
	:so=: :se=:	start/end standout mode (We don't care about :sg#:)
	:us=: :ue=:	start/end underlined mode
	:VB=: :Vb=:	start/end boldface mode
	:as=: :ae=:	start/end alternate character set (italics)
	:ug#:		visible gap left by :us=:, :ue=:, :VB=:, or :Vb=:
