[doc] update news
[doc] remove references to extralibs and typo-krn from manual
[main] adapt initialization
[doc] erase references to typo-krn and extralibs from file graph
[doc] don’t mention mkluatexfontdb.lua in file graph
[status] update file list
[letterspace] move to luaotfload.letterspace namespace
[doc] document letterspacing