le_util cleanup, le_util_test
Fix JOSE encoding mess
Better tests for jose b64 padding
Allow unicode input for JOSE Base64
Remove heisenbug from acme_test
py26 doesn't support set {} constructor. Use frozenset.
Merge remote-tracking branch 'github/master' into le_util_test

Conflicts:
	letsencrypt/client/client.py
	letsencrypt/client/crypto_util.py
Add utility functions for checking CSR and privkey
Merge pull request #74 from kuba/py26-compat

py26 doesn't support set {} constructor. Use frozenset.
Merge remote-tracking branch 'github/master' into le_util_test
JOSE Base64: encode str only, decode str or ascii unicode
TODO encode? comments for jose_b64encode
Fix TODO encode? in create_sig

- n, e are `int`s, applied transformations make it `str`

- Crypto.Signature.PKCS1_v1_5.new [1] returns PKCS115_SigScheme, and its
  `sign()` method returns `str` [2]

- docs is OK: requires `nonce` to be `str`

- `create_sig` is not called with custom `nonce` argument anywhere in
  the code

[1] https://www.dlitz.net/software/pycrypto/api/2.6/Crypto.Signature.PKCS1_v1_5-module.html#new
[2] https://www.dlitz.net/software/pycrypto/api/2.6/Crypto.Signature.PKCS1_v1_5.PKCS115_SigScheme-class.html#sign
Fix TODO encode? in apache_configurator.

`s = Random.get_random_bytes(CONFIG.S_SIZE)`, so `s` is `str`.
Fix TODO encode? in acme.py
Merge pull request #73 from kuba/acme_test_pretty_heisenbug

Remove heisenbug from acme_test
Merge pull request #72 from kuba/le_util_test

le_util cleanup, le_util_test, docs
Add documentation for parameters of new functions
Integrate CSR and private key validation steps into client
PEP8 formatting fixes