fix bug in word array containment check (prog8_lib.containment_wordarray) that could hang the loop

compiler/res/prog8lib/prog8_lib.asm

@@ -1082,6 +1082,7 @@ containment_wordarray	.proc
 		iny
 		cmp  (P8ZP_SCRATCH_W2),y
 		beq  _found
+		dey
 +		dey
 		dey
 		cpy  #254

docs/source/todo.rst

@@ -3,14 +3,6 @@ TODO
 
 For next release
 ^^^^^^^^^^^^^^^^
-- fix compiler error about containment
-                    if xx[idx]==0 or xx[idx]==319 {
-                        ; nothing here, if a call is here the error doesn't trigger !??
-                        ; gfx2.plot(xx[idx], yy[idx], PILED_SNOW_COLOR)
-                    } else {
-                        ...
-                    }
-
 - 6502 codegen: make it possible to use cpu opcodes such as 'nop' as variable names by prefixing all asm vars with something such as ``p8v_``? Or not worth it (most 3 letter opcodes as variables are nonsensical anyway)
   then we can get rid of the instruction lists in the machinedefinitions as well.  This is already no problem at all in the IR codegen.
 - create BSS section in output program and put StStaticVariables in there with bss=true. Don't forget to add init code to zero out everything that was put in bss. If array in bss->only zero ONCE! So requires self-modifying code