Allowing access to globals while in a loop

This used to make a name like DATA.0.STR.  Since bash doesn't like using
multi-dimensional arrays, we can shortcut things and just assume that
STR referes to the global variable here.

This closes issue #7

tests/globals-in-loop.env

@@ -0,0 +1,2 @@
+STR=abc
+DATA=(111 222)

tests/globals-in-loop.expected

@@ -0,0 +1,6 @@
+Issue #7
+abc
+    Item: 111
+    String: abc
+    Item: 222
+    String: abc

tests/globals-in-loop.template

@@ -0,0 +1,6 @@
+Issue #7
+{{STR}}
+{{#DATA}}
+    Item: {{.}}
+    String: {{STR}}
+{{/DATA}}