Added M2crypto.

Uses m2crypto to obtain signature algorith, size, issuer, serial,
common-name, subject-alternative-name, domains, valid_before, and
valid_after.

Fixed the slurp_exception region so an exception will now correctly
prevent the change watcher from identifying changes when an exception is
thrown.

Installing m2crypto can be a pain.  The following commands seem to work:
```sudo apt-get install swig; pip install m2crypto```.  It may be
required to run ```sudo apt-get install python-m2crypto```.
Removing re package and obtaining signature-algorithm in the same way as the other attributes
Adding IAM SSL checks for cert size and signing algorithm hash
Minor documentation fix
Merge branch 'feature/adding_m2crypto_to_iamssl' into develop
Using botocore to obtain listener policies. Checking reference policy and custom policies for protocol and deprecated ciphers.
Locking down versions of botocore and m2crypto
Adding expiration checks and an upload-date check for heartbleed
Updating docs to install swig and python-m2crypto
Flag on RC4 ciphers in custom listener policies
Merge pull request #88 from monkeysecurity/develop

Monitor ELB Listener Policies and IAM SSL cert size and signature algorithm and expiration and upload-date.