Added info on .gitignore

Author: rijnb

README.md

@@ -30,3 +30,24 @@ limitations under the License.
 Original C library created by Pieter Geelen. Work on Java version
 of the mapcode library by Rijn Buve and Matthew Lowden.
 
+# Using Git and .gitignore
+
+It's good practice to set up a personal global .gitignore file on your machine which filters a number of files
+on your file systems that you do not wish to submit to the Git repository. You can set up your own global
+.gitignore file by executing:
+`git config --global core.excludesfile ~/.gitignore`
+
+In general, filter these file types in `~/.gitignore` (each entry should be on a separate line):
+`*.com *.class *.dll *.exe *.o *.so *.log *.sql *.sqlite *.tlog *.epoch *.swp *.hprof *.hprof.index *~`
+
+If you're using a Mac, filter:
+`.DS_Store* Thumbs.db`
+
+If you're using IntelliJ IDEA, filter:
+`*.iml *.iws *.releaseBackup .idea/`
+
+If you're using Eclips, filter:
+`.classpath .project .settings .cache`
+
+If you're using NetBeans, filter: 
+`nb-configuration.xml *.orig`