fix typo
Update lang.php

add ```fillmath``` key/value
Update lang.php
Update settings.php

add ```mode_o_math``` key/value
Merge pull request #10 from mprins/translation_update

NL translation update
Japanese translation
Merge pull request #11 from nyantama/japanese-translation

Add Japanese translation.
bind captcha to current day
some cosmetic code cleanup
allow user to set the length of the CAPTCHA
obfuscate plain text

When the CAPTCHA code is in plain text in the HTML code (js, text,
math), random whitespace characters are introduced inbetween. This
should make it a little bit harder to parse the code from the HTML
source.
update simplified Chinese translation
can translate the honeypot message
Merge branch 'i18N'
update simplified Chinese translation