bunzip2: add page

[KristopherLeads]

• 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):

[tldr-bot]

The build for this PR failed with the following error(s):

pages/common/bunzip2.md:27: TLDR005 Example descriptions should end in a colon with no trailing characters

Please fix the error(s) and push again.

[acuteenvy]

bunzip2 is a symlink to bzip2 and works exactly like bzip2 -d. This should be an alias page (like unxz for example).

https://manned.org/bunzip2

-d --decompress
Force decompression. bzip2, bunzip2 and bzcat are really the same
program, and the decision about what actions to take is done on
the basis of which name is used.

Suggested change

	> Decompress a file and save by overwriting the original compressed file.
	> See also: `bzip2`, `bzcat`, `bzip2recover`.
	> More information: <https://manned.org/bunzip2>.
	- Decompress a file and stream to standard output:
	`bunzip2 {{file.bz2}}`
	- Test integrity of compressed file:
	`bunzip2 {{[-t|--test]}} {{file.bz2}}`
	- Hide all non-essential output messages, errors, and warnings:
	`bunzip2 {{[-q|--quiet]}} {{file.bz2}}`
	- Reduce decompression memory usage by reducing speed:
	`bunzip2 {{[-s|--small]}} {{file.bz2}}`
	- Reduce decompression memory usage by reducing speed:
	`bunzip2 {{[-k|--keep]}} {{file.bz2}}`
	- Override file overwrite and keep the original compressed file:
	`bunzip2 {{[-V|--version]}}`
	> This command is an alias of `bzip2 --decompress`.
	- View documentation for the original command:
	`tldr bzip2`

[KristopherLeads]

There is a wrinkle in that it's not a true alias - what you can call changes the function of the command. They can be invoked as an alias would but simply evoking one form only invokes one specific behavior.

[Managor]

How does that differ from unxz?