Update gitk.md

pages/linux/gitk.md

@@ -1,7 +1,23 @@
 # gitk
 
-> A git GUI tool.
+> A graphical git repository browser.
 
 - Show repository browser in current git repository:
 
-`gitk --all`
+`gitk`
+
+- Show repository browse of a specific file or folder:
+
+`gitk {{path/to/file_or_folder}}`
+
+- Show commits since 1 week ago:
+
+`gitk --since="1 week ago"` 
+
+- Show commits older than 1/1/2016
+
+`gitk --until="1/1/2015"`
+
+- Show at most 100 changes in all branches:
+
+` gitk --max-count=100 --all`