doc: update docs and sample files

doc/sample/ForLoop.mie

@@ -1,31 +1,15 @@
-data @cout = external global id
+ivy.module @test {
+	%cout = ivy.global-ref @cout
 
-data @.str.0 = str "hello"
+	ivy.init-text {
+		%str = ivy.str.constant "hello"
+		%.str.0 = ivy.str.constant "done"
 
-define void @init() static {
-entry:
-	%0 = load str, ptr @.str.0
-	%str = alloca id
-	store str %0, ptr %str
+		ivy.for-each %c in %str {
+			ivy.msg to %cout, -put:%c
+		}
 
-	%1 = load id, ptr %str
-	%for.it = msg id, id %1, @_M8iteratorE
-	br label %for.cond
-for.cond:
-	%for.value = msg id, id %for.it, @_M5valueE
-	%for.finished = cmp eq id %for.value, null
-	br i1 %for.finished, label %for.end, label %for.body
-for.body:
-	%c = alloca id
-	store id %for.value, ptr %c
+		ivy.msg to %cout, -put:%.str.0
 
-	%2 = load id, ptr @cout
-	%3 = load id, ptr %c
-	msg void, id %2, @_M03putE [ id %3 ]
-	br label %for.inc
-for.inc:
-	msg void, id %for.it, @_M8moveNextE
-	br label %for.cond
-for.end:
-	ret void
+	}
 }