implement FREADUY on pet, so that ubyte to float now works

compiler/res/prog8lib/pet32/floats.p8

@@ -19,7 +19,6 @@ const uword FAC_ADDR = $5e
 ;extsub $ba90 = FAREADMEM() clobbers(A,Y)                    ; load mflpt value from memory  in $22/$23 into fac2
 ;;
 ;
-;extsub $b3a2 = FREADUY(ubyte value @ Y) clobbers(A,X,Y)     ; 8 bit unsigned Y -> float in fac1
 ;extsub $b7b5 = FREADSTR(ubyte length @ A) clobbers(A,X,Y)   ; str -> fac1, $22/23 must point to string, A=string length.  Also see parse()
 ;extsub $aabc = FPRINTLN() clobbers(A,X,Y)                   ; print string of fac1, on one line (= with newline) destroys fac1.  (consider FOUT + STROUT as well)
 ;
@@ -101,6 +100,15 @@ asmsub  AYINT2() clobbers(X) -> word @AY {
     }}
 }
 
+asmsub FREADUY(ubyte value @ Y) clobbers(A,X,Y) {
+    ; -- 8 bit unsigned Y -> float in fac1
+    %asm {{
+        lda  #0
+        jmp  GIVAYF
+    }}
+}
+
+
 asmsub  FREADSA  (byte value @A) clobbers(A,X,Y) {
     ; ---- 8 bit signed A -> float in fac1
     %asm {{

docs/source/todo.rst

@@ -13,6 +13,7 @@ Future Things and Ideas
 - make builtin functions capable of returning multiple values, then make divmod() return the 2 results rather than accepting 2 extra variables as arguments
 - then also introduce lmh(longvalue) -or whatever sensible name- builtin function that returns the low, mid, hi (bank) bytes of a long.
 - and rewrite the divmod (and others?) function to just return the 2 results instead of taking target variables as arguments.
+- allow alias to blocks?
 - add a -profile option (for now X16 only) that instruments the start (and returns?) -of every prog8 subroutine with code that dumps to the X16 emulator debug console: name of sub, stack pointer (for call depth!), emudbg cycle count. Save/restore all used registers!  Start of program must set cycle count to zero.
 - add @private to variables and subroutines declared in a scope to make them invisible from outside that scope?
 - when implementing unsigned longs: remove the (multiple) "TODO "hack" to allow unsigned long constants to be used as values for signed longs, without needing a cast"