[S07] change .push example (which doesn't follow one-arg rule) to .ap…

…pend.

As discussed - closes #104

S07-lists.pod

@@ -77,14 +77,14 @@ The single argument rule does respect C<Scalar> containers. Therefore:
     for $@a { }             # Array in a Scalar; 1 iteration
 
 The single argument rule is implemented consistently throughout the language.
-For example, consider the C<push> method:
-
-    @a.push: 1, 2, 3;       # pushes 3 values to @a
-    @a.push: [1, 2, 3];     # pushes 3 values to @a
-    @a.push: @b;            # pushes @b.elems values to @a
-    @a.push: @b,;           # same, trailing comma doesn't make > 1 argument
-    @a.push: $(1, 2, 3);    # pushes 1 value (a List) to @a
-    @a.push: $[1, 2, 3];    # pushes 1 value (an Array) to @a
+For example, consider the C<append> method:
+
+    @a.append: 1, 2, 3;       # appends 3 values to @a
+    @a.append: [1, 2, 3];     # appends 3 values to @a
+    @a.append: @b;            # appends @b.elems values to @a
+    @a.append: @b,;           # same, trailing comma doesn't make > 1 argument
+    @a.append: $(1, 2, 3);    # appends 1 value (a List) to @a
+    @a.append: $[1, 2, 3];    # appends 1 value (an Array) to @a
 
 Additionally, the list constructor (the C<< infix:<,> >> operator) and the
 array composer (the C<[...]> circumfix) follow the rule: