'type' is problematic as it conflicts with a default field name
in logstash.
Bug: T145133
Change-Id: Idb73ba3e431ef2bd25b14c8562d1b3f212b4e072
Depends-On: Iab1eb47a6b6c98f3c84b4f8e2d16cbe2cdbf515b
Also remove references to "two words" from ReCaptcha labels.
The captcha image doesn't always contain two words.
Bug: T110302
Change-Id: I544656289480056152a1db195babb6dadf29bc71
Also update MathCaptcha so that it works with recent versions of
Math (and breaks with old ones). Also fix MathCaptcha API output,
which used to send the question in plaintext.
Bug: T110302
Change-Id: I0da671a546700110d789b79a3089460abd9cce3b
Depends-On: I8b52ec8ddf494f23941807638f149f15b5e46b0c
