Modernize .gitignore file

.gitignore

@@ -1,36 +1,24 @@
-# See http://help.github.com/ignore-files/ for more about ignoring files.
-#
-# If you find yourself ignoring temporary files generated by your text editor
-# or operating system, you probably want to add a global ignore instead:
-#   git config --global core.excludesfile ~/.gitignore_global
-
-# Ignore bundler config
+# Ignore bundler config.
 /.bundle
 
 # Ignore all logfiles and tempfiles.
-/log/*.log
-/tmp
+/log/*
+!/log/.keep
+/tmp/*
+!/tmp/.keep
 
-# Ignore .vagrant folder with images
-.vagrant
-.metadata
+# Ignore uploaded files in development.
+/storage/*
+!/storage/.keep
 
-# CTAGS generated files
-.tags
-tags
+# Ignore master key for decrypting credentials and more.
+/config/master.key
 
-# Misc
-*.rbc
-*.sassc
-**.orig
-.sass-cache
-capybara-*.html
-/vendor/bundle
+# Ignore compiled assets and node_modules
+/app/assets/builds/*
+!/app/assets/builds/.keep
 /public/assets
-/storage/
-/coverage/
-/spec/tmp/*
-.byebug_history
+/node_modules
+
+# Ignore ENV files
 .env
-.DS_Store
-.idea/