warn user about exposing email address when creating message
Merge pull request #873 from xi/feature-warn-email

warn user about exposing email address when creating message
replace only specific message variables

this avoids errors when using {} in message strings
Merge pull request #875 from xi/feature-fix-message-variables

replace only specific message variables
i18n
Avoid uneccessare delegateable invalidation

When invalidating instances, each delegeteable in that instance is
invalidated. So there is no need to invalidate the parent delegateables
or the instance again.

I guess more optimization could be done here. This speed up proposal
creation by about 15x on my test installation.
[build.sh] Make distro tests exclusive

Apparently, some versions of Ubuntu do have a yum binary, but it's really not functional (and shouldn't be used).
csslint
pep8
Move captcha to proper section in register form
Fix recaptcha.net instructions
Add captchas.net python module

This is from http://captchas.net/sample/python/CaptchasDotNet.py
Add missing import in captchas.net python module
pep8 captchas.net python module
Remove link from captchas.net image

This link is disturbing to users. The attribution banner is still
displayed.
Add captchas.net captcha verification

Due to privacy and usability concerns, captchas.net is added as another
captcha solution besides reCAPTCHA.

This makes use of the provided python module on captchas.net [0],
however only uses parts of its functionality. In particular, we use the
pylons session to store the random tokens instead of files. These files
are however still created and cleaned up without any need.

[0] http://captchas.net/sample/python/captchasdotnet
Merge pull request #876 from xi/feature-avoid-uneccessary-invalidation

Avoid uneccessary delegateable invalidation
Document other captchas.net configuration options
Merge pull request #878 from nidico/feature-captchas-dot-net

Add captchas.net captcha verification
Add adhocracy configuration stub section in INSTALLATION.rst

Propose to create an own buildout-my buildout config instead of using
the default buildout.cfg. This avoids merge conflicts when upgrading
Adhocracy.