Use ATOM_HOME when building cache path

src/6to5.coffee

@@ -96,7 +96,7 @@ getCachePath = (sourceCode) ->
 
   unless jsCacheDir?
     to5Version = require('6to5-core/package.json').version
-    cacheDir = path.join(fs.absolute('~/.atom'), 'compile-cache')
+    cacheDir = path.join(process.env.ATOM_HOME, 'compile-cache')
     jsCacheDir = path.join(cacheDir, 'js', '6to5', create6to5VersionAndOptionsDigest(to5Version, defaultOptions))
 
   path.join(jsCacheDir, "#{digest}.js")

src/coffee-cache.coffee

@@ -5,7 +5,7 @@ CoffeeScript = require 'coffee-script'
 CSON = require 'season'
 fs = require 'fs-plus'
 
-cacheDir = path.join(fs.absolute('~/.atom'), 'compile-cache')
+cacheDir = path.join(process.env.ATOM_HOME, 'compile-cache')
 
 stats =
   hits: 0