Remove BROWSE and CASE

With the Visual Editor, BROWSE is of dubious value. Even before that,
it was of dubious value. It's the only user of the CASE word, which
is also of dubious value: too complicated for its own good.

The CMD pattern used in VE is much better.

blk/100

@@ -3,14 +3,4 @@ Block editor
 This is an application to conveniently browse the contents of
 the disk blocks and edit them. You can load it with "105 LOAD".
 
-Browse mode: If you execute BROWSE, the Forth interpreter is
-replaced by browser's loop. Typing "Q" quits the browser.
-
-In this mode, typing a decimal number followed by space or
-return lists the contents of that block. B for previous block,
-N for next.
-
-When not in browse mode, your prompt is a regular Forth prompt
-with editor words loaded.
-
-                                                        (cont.)
+See doc/ed.txt

blk/101

@@ -1,16 +0,0 @@
-There are two buffers, IBUF (insert buffer) and FBUF (find
-buffer). They are used as a typing target for the actions
-described below. They both have a peculiar logic: when typing
-is expected to fill a buffer, an empty value means "reuse
-previous value". For example, typing "I foo I " inserts
-"foofoo".
-
-T ( n -- ): select line n for editing.
-P xxx: put typed IBUF on selected line.
-U xxx: insert typed IBUF on selected line.
-F xxx: find typed FBUF in block, starting from current
-       position+1. If not found, don't move.
-i xxx: insert typed IBUF at cursor. "i" is to avoid shadowing 
-       core word "I".   
-Y: Copy n characters after cursor into IBUF, n being length of
-   FBUF.                                                (cont.)

blk/102

@@ -1,2 +0,0 @@
-X ( n -- ): Delete X chars after cursor and place in IBUF.
-E: Run X with n = length of FBUF.

blk/105

@@ -1,14 +1,2 @@
-'? CASE NOT [IF] 48 49 LOADR+ [THEN] DROP ( B153-154 )
 '? FILL NOT [IF] 50 LOAD+ [THEN] DROP ( B155 )
 1 7 LOADR+
-: BROWSE
-    0 ACC ! L
-    BEGIN
-        KEY CASE
-            'Q' OF EXIT ENDOF
-            'B' OF B ENDOF
-            'N' OF N ENDOF
-            _NUM
-        ENDCASE
-    AGAIN
-;

blk/152

@@ -1,3 +1,2 @@
-'? CASE NOT [IF] 1 2 LOADR+ [THEN] DROP ( from '? )
 '? FILL NOT [IF] 3 LOAD+ [THEN] DROP
 '? WIPE NOT [IF] 5 LOAD+ [THEN] DROP

blk/153

@@ -1,9 +0,0 @@
-( During a CASE, the stack grows by 1 at each ENDOF so that
-  we can fill all those ENDOF branching addrs. So that we
-  know when to stop, we put a 0 on PSP. That's our stopgap. )
-: CASE 0 ; IMMEDIATE
-: OF
-    COMPILE OVER COMPILE =
-    [COMPILE] IF COMPILE DROP
-; IMMEDIATE
-: ENDOF [COMPILE] ELSE ; IMMEDIATE

blk/154

@@ -1,9 +0,0 @@
-( At this point, we have something like "0 e1 e2 e3 val". We
-  want to drop val, and then call THEN as long as we don't
-  hit 0. )
-: ENDCASE
-    BEGIN
-        ?DUP NOT IF EXIT THEN
-        [COMPILE] THEN
-    AGAIN
-; IMMEDIATE

tests/cvm/test_flow.fs

@@ -1,15 +0,0 @@
-152 LOAD ( extra )
-: foo
-    CASE
-        'X' OF 42 ENDOF
-        0x12 OF 43 ENDOF
-        255 OF 44 ENDOF
-        1+
-    ENDCASE
-;
-
-'X' foo 42 #eq
-0x12 foo 43 #eq
-255 foo 44 #eq
-254 foo 255 #eq
-'S S0 #eq