Specify R repos in RKorAPClient installation instructions

Change-Id: Ide18535c08aa0f501622f93607602df437303b43
diff --git a/Readme.md b/Readme.md
index 7af894c..42031b5 100644
--- a/Readme.md
+++ b/Readme.md
@@ -32,7 +32,7 @@
 
 #### 3. Install the R package
 ```
-Rscript -e "install.packages('RKorAPClient')"
+Rscript -e "install.packages('RKorAPClient', repos='https://cloud.r-project.org/')"
 ```
 #### 4. Install the Python package
 ```