Add explanations to use exact url flag to Readme

README.md

@@ -35,6 +35,7 @@ Download an entire website from the Wayback Machine.
 					     Default is ./websites/ plus the domain name
 	    -f, --from TIMESTAMP             Only files on or after timestamp supplied (ie. 20060716231334)
 	    -t, --to TIMESTAMP               Only files on or before timestamp supplied (ie. 20100916231334)
+	    -e, --exact_url                  Download only the url provied and not the full site
 	    -o, --only ONLY_FILTER           Restrict downloading to urls that match this filter
 					     (use // notation for the filter to be treated as a regex)
 	    -x, --exclude EXCLUDE_FILTER     Skip downloading of urls that match this filter
@@ -44,11 +45,12 @@ Download an entire website from the Wayback Machine.
 					     Default is one file at a time (ie. 20)
 	    -p, --maximum-snapshot NUMBER    Maximum snapshot pages to consider (Default is 100)
 					     Count an average of 150,000 snapshots per page
-	    -l, --list                       Only list file urls in a JSON format with the archived timestamps, won't download anything.
+	    -l, --list                       Only list file urls in a JSON format with the archived timestamps, won't download anything
 	    -v, --version                    Display version
 
 
 
+	    
 ## Specify directory to save files to
 
     -d, --directory PATH
@@ -81,6 +83,17 @@ Example:
 
     wayback_machine_downloader http://example.com --to 20100916231334
     
+## Exact Url
+
+	-e, --exact_url 
+
+Optional. If you want to retrieve only the file matching exactly the url provided, you can use this flag. It will avoid downloading anything else.
+
+For example, if you only want to download only the html homepage file of example.com:
+
+    wayback_machine_downloader http://example.com --exact_url 
+
+
 ## Only URL Filter
 
      -o, --only ONLY_FILTER