Make sure label text is escaped if it is not safe

Signed-off-by: Rafael Mendonça França <rafaelmfranca@gmail.com>
Make sure hint text is escaped if it is not safe

Signed-off-by: Rafael Mendonça França <rafaelmfranca@gmail.com>
Make sure error_prefix option is escaped if it is not safe

Signed-off-by: Rafael Mendonça França <rafaelmfranca@gmail.com>
Allow item_wrapper_tag to be blank instead of falling
back to a span
Ability to pass the input to the block when using
f.input and f.input_field