Rename |peg$cache| to |peg$resultsCache|

This change will make the results cache clearly distinguishable from the
position details cache (which I'll add in a minute).

lib/compiler/passes/generate-javascript.js

@@ -56,7 +56,7 @@ function generateJavascript(ast, options) {
     if (options.cache) {
       parts.push([
         'var key    = peg$currPos * ' + ast.rules.length + ' + ' + ruleIndexCode + ',',
-        '    cached = peg$cache[key];',
+        '    cached = peg$resultsCache[key];',
         '',
         'if (cached) {',
         '  peg$currPos = cached.nextPos;',
@@ -99,7 +99,7 @@ function generateJavascript(ast, options) {
     if (options.cache) {
       parts.push([
         '',
-        'peg$cache[key] = { nextPos: peg$currPos, result: ' + resultCode + ' };'
+        'peg$resultsCache[key] = { nextPos: peg$currPos, result: ' + resultCode + ' };'
       ].join('\n'));
     }
 
@@ -897,7 +897,7 @@ function generateJavascript(ast, options) {
 
   if (options.cache) {
     parts.push([
-      '        peg$cache = {},',
+      '        peg$resultsCache = {},',
       ''
     ].join('\n'));
   }