vowpal-wabbit 8.0

Upgrade vowpal-wabbit to 8.0

Lots of new features.  Some of the cool ones are:
    - Online gradient boosting trees for binary classification
    - Online follow-the-regularized-leader optimization
    - Field-aware low-rank quadratic features (similar to libFFM)
    - Lots of bug fixes, including processing older model files

Closes #41455.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Library/Formula/vowpal-wabbit.rb

@@ -4,8 +4,8 @@ class VowpalWabbit < Formula
   desc "Online learning algorithm"
   homepage "https://github.com/JohnLangford/vowpal_wabbit"
   head "https://github.com/JohnLangford/vowpal_wabbit.git"
-  url "https://github.com/JohnLangford/vowpal_wabbit/archive/7.10.tar.gz"
-  sha1 "66f476926c760d5b604057796f7e19c52d7702a8"
+  url "https://github.com/JohnLangford/vowpal_wabbit/archive/8.0.tar.gz"
+  sha1 "a83b37851d8743358339d3dfa1342b3c1caef18b"
 
   bottle do
     cellar :any