build, data: skk2ktrans keeps the SKK header; the recipe names every generator; an inert config line goes

An SKK dictionary's ";;" header carries its license notice, which
LICENSES/README.md relies on for kanji.dict, and skk2ktrans dropped
every ";;" line: a re-import as map/README describes lost the grant.
The leading comment block is kept now.  README's regenerate-and-verify
recipe omitted mktelex.py although verify-map checks its output; and
the Dockerfile set a shell variable named egrep in plan9's config that
9c never reads, calling egrep by name.

map/skk2ktrans

@@ -36,10 +36,16 @@ function add(k, v, id) {
 		row[k] = row[k] " "
 	row[k] = row[k] v
 }
-/^;;/ || /^[[:space:]]*$/ {
+/^;;/ {
+	if(!body)		# the header, with its license notice, is kept
+		print
+	next
+}
+/^[[:space:]]*$/ {
 	next
 }
 {
+	body = 1
 	if(!match($0, /[[:space:]]+/))
 		fail("missing candidate list")
 	key = substr($0, 1, RSTART-1)