~: add page

[Managor]

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page(s) have at most 8 examples.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known):

[Managor]

gnu.org is down currently. I'll fetch the specific manual entry later

There were other ~ tricks like ~+ which is the exact same as . and thus obsolete and ~1 which is used in combination with pushd which I didn't feel like including.