Improved CodeIgniter .gitignore to support an system directory in a different...

Improved CodeIgniter .gitignore to support an system directory in a different location to the default install. Fixed database.php ignore rule. The application directory can be moved to any location and the ignore will still operate

CodeIgniter.gitignore

-config/database.php
-system/logs/log-*.php
-system/cache/*
-systen/cache/!index.html
+*/config/database.php
+*/system/logs/log-*.php
+*/system/cache/*
+*/systen/cache/!index.html