Fix FilterProvider in .htaccess in Apache 2.4

Apache 2.4 configuration on FilterProvider changed.
This generate a problem of Internal server error 500 in Apache 2.4.

In this commit, I added a IfVersion into the htaccess to help check
Apache version before doing FilterProvider
Details of Apache’s change:
http://httpd.apache.org/docs/2.4/upgrading.html