Switched to PyCrypto and pyramid.

- Switched from `M2Crypto` to `PyCrypto`, since `M2Crypto` is not maintained
  anymore.

- Switched from deprecated `repoze.bfg` to `pyramid`.

NOTE: While I found code online to make the switch from `PyCrypto` to
`M2Crypto` backwards compatible, I have not tested that functionality.
Please try this on your data and let me know if you have issues.

NOTE 2: `PyCrypto` does not allow 512-bit RSA keys, so I increased the key
size to 2048 bits. Old 512-bit keys should still work, but new ones will be
always larger now.

.gitignore

@@ -0,0 +1,8 @@
+*.pyc
+__pycache__
+src/*.egg-info
+.installed.cfg
+bin
+coverage
+develop-eggs
+parts