Fix 500 when saving /site/edit without email
When saving /site/edit with no no_reply_email set, a 500 error page
would be returned due to an empty value being passed as value to
the datastore (which is not allowed for email fields).
# The INCLUDE and LIB directories to build the '_yaml' extension.
# You may also set them using the options '-I' and '-L'.
[build_ext]
# List of directories to search for 'yaml.h' (separated by ':').
#include_dirs=/usr/local/include:../../include
# List of directories to search for 'libyaml.a' (separated by ':').
#library_dirs=/usr/local/lib:../../lib
# An alternative compiler to build the extention.
#compiler=mingw32
# Additional preprocessor definitions might be required.
#define=YAML_DECLARE_STATIC
# The following options are used to build PyYAML Windows installer
# for Python 2.3 on my PC:
#include_dirs=../../libyaml/trunk/include
#library_dirs=../../libyaml/trunk/win32/vc6/output/release/lib
#define=YAML_DECLARE_STATIC
# The following options are used to build PyYAML Windows installer
# for Python 2.4 and Python 2.5 on my PC:
#include_dirs=../../libyaml/trunk/include
#library_dirs=../../libyaml/trunk/win32/vs2003/output/release/lib
#define=YAML_DECLARE_STATIC