Bug 1147283 - Replace mozpack.path with mozpath. r=mshal

Back when mozpack.path was added, it was used as:

  import mozpack.path
  mozpack.path.func()

Nowadays, the common idiom is:

  import mozpack.path as mozpath
  mozpath.func()

because it's shorter.

$ git grep mozpath\\. | wc -l
423
$ git grep mozpack.path\\. | wc -l
123

This change was done with:
$ git grep -l mozpack.path\\. | xargs sed -i 's/mozpack\.path\./mozpath./g'
$ git grep -l 'import mozpack.path$' | xargs sed -i 's/import mozpack.path$/\0 as mozpath/'
$ (pat='import mozpack.path as mozpath'; git grep -l "$pat" | xargs sed -i "1,/$pat/b;/$pat/d")

python/mozbuild/mozpack/test/test_files.py

@@ -37,7 +37,7 @@ import os
 import random
 import string
 import sys
-import mozpack.path
+import mozpack.path as mozpath
 from tempfile import mkdtemp
 from io import BytesIO
 from xpt import Typelib
@@ -870,7 +870,7 @@ class MatchTestTemplate(object):
                                                 finder.find(pattern)])
             self.assertEqual(sorted([f for f, c in finder.find(pattern)]),
                              sorted([f for f, c in finder
-                                     if mozpack.path.match(f, pattern)]))
+                                     if mozpath.match(f, pattern)]))
 
 
 def do_check(test, finder, pattern, result):