Merge pull request #1684 from jimhester/patch-1

Ignore output from R CMD build and R CMD check

R.gitignore

@@ -8,6 +8,12 @@
 # Example code in package build process
 *-Ex.R
 
+# Output files from R CMD build
+/*.tar.gz
+
+# Output files from R CMD check
+/*.Rcheck/
+
 # RStudio files
 .Rproj.user/