Adding .hgignore based on the .gitignore.

git-svn-id: https://svn.redmine.org/redmine/trunk@4606 e93f8b46-1217-0410-a6f0-8f06a7374b81

.hgignore

+syntax: glob
+
+config/additional_environment.rb
+config/database.yml
+config/email.yml
+config/initializers/session_store.rb
+coverage
+db/*.db
+db/*.sqlite3
+db/schema.rb
+files/*
+log/*.log*
+log/mongrel_debug
+public/dispatch.*
+public/plugin_assets
+tmp/*
+tmp/cache/*
+tmp/sessions/*
+tmp/sockets/*
+tmp/test/*
+vendor/rails
+*.rbc