remove os.access usage

[Ramereth]

As requested by ferringb in #pkgcore, Please remove os.access usage in pkgcore as there are some issues with it on SunOS. Specifically, os.access(filename, os.X_OK) does not return the proper test case on solaris. If you need more information, please let me know!

[Ramereth]

For documentation sake, here's the output of the test case:

======================================================================

FAIL: test_find_binary (pkgcore.test.test_spawn.SpawnTest)

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Traceback (most recent call last):

  File "/usr/lib/python2.4/site-packages/snakeoil/test/__init__.py", line 171, in run

    self.forced_extra_frame(testMethod)

  File "/usr/lib/python2.4/site-packages/snakeoil/test/__init__.py", line 140, in forced_extra_frame

    test()

  File "/tmp/pkgcore-0.4.5/pkgcore/test/test_spawn.py", line 43, in test_find_binary

    self.assertRaises(spawn.CommandNotFound, spawn.find_binary, script_name)

AssertionError: CommandNotFound not raised



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And as a simple test:

root@poplar / # touch foon; chmod 0640 foon; python -c 'import os;print os.access("foon", os.X_OK)'
True
root@poplar / # ls -l foon
-rw-r-----   1 root     101            0 Apr 21 17:06 foon

So something is lying :-)

[ferringb]

Bleh. this will be 0.4.7, sorry.

Got a set of fixups/features want to release, and frankly I don't want to replace access quite yet (mainly since I'm dreading the logic ;). Will attach a patch w/in a few days.