.gitignore in chronicle-etl-0.2.4 vs .gitignore in chronicle-etl-0.3.0

@@ -5,8 +5,11 @@
 /doc/
 /pkg/
 /spec/reports/
 /tmp/
 
+# https://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/
+Gemfile.lock
+
 # rspec failure tracking
 .rspec_status
 .DS_Store
\ No newline at end of file