git-annex: add page (#4421)

pages/common/git-annex.md

@@ -0,0 +1,29 @@
+# git annex
+
+> Manage files with git, without checking their contents in.
+> When a file is annexed, its content is moved into a key-value store, and a symlink is made that points to the content.
+> More information: <https://git-annex.branchable.com>.
+
+- Help:
+
+`git annex help`
+
+- Initialize a repo with git annex:
+
+`git annex init`
+
+- Add a file:
+
+`git annex add {{path/to/file_or_directory}}`
+
+- Show the current status of a file or directory:
+
+`git annex status {{path/to/file_or_directory}}`
+
+- Synchronize a local repository with a remote:
+
+`git annex {{remote}}`
+
+- Get a file or directory:
+
+`git annex get {{path/to/file_or_directory}}`