[ci skip] Merge pull request #5859 from indrakaw/gitattributes
[ci skip] Merge pull request #5859 from indrakaw/gitattributes

Exclude user_guide directory from composer installation by GitAttributes.

This would allow Composer users to use --prefer-dist in order to avoid downloading the entire user guide
bcit-ci/CodeIgniter,madwings/InsaneDB,butane/CodeIgniter,butane/CodeIgniter,madwings/InsaneDB,madwings/InsaneDB,butane/CodeIgniter,butane/CodeIgniter,bcit-ci/CodeIgniter,bcit-ci/CodeIgniter,bcit-ci/CodeIgniter,madwings/InsaneDB,madwings/InsaneDB,bcit-ci/CodeIgniter,butane/CodeIgniter