Base: Add a manpage for 'printf'

Author: https://github.com/alimpfard
Commit: https://github.com/SerenityOS/serenity/commit/0341e3fde73
Pull-request: https://github.com/SerenityOS/serenity/pull/3814
Reviewed-by: https://github.com/bugaevc

Base/usr/share/man/man1/printf.md

@@ -0,0 +1,53 @@
+## Name
+
+printf - format and print data
+
+## Synopsis
+
+```**sh
+printf <format> [arguments...]
+```
+
+## Description
+
+`printf` formats _argument_(s) according to _format_ and prints the result to standard output.
+
+_format_ is similar to the C printf format string, with the following differences:
+- The format specifier `b` (`%b`) is not supported.
+- The format specifiers that require a writable pointer (e.g. `n`) are not supported.
+- The format specifier `q` (`%q`) has a different behaviour, where it shall print a given string as a quoted string, which is safe to use in shell inputs.
+- Common escape sequences are interpreted, namely the following:
+
+| escape | description |
+|   :-:  |    :---     |
+|  `\\\\`| literal backslash |
+|  `\\"` | literal double quote |
+|  `\\a` | alert (BEL) |
+|  `\\b` | backspace |
+|  `\\c` | Ends the format string |
+|  `\\e` | escape (`\\x1b`) |
+|  `\\f` | form feed |
+|  `\\n` | newline |
+|  `\\r` | carriage return |
+|  `\\t` | tab |
+|  `\\v` | vertical tab |
+
+
+The _format_ string is reapplied until all arguments are consumed, and a missing argument is treated as zero for numeric format specifiers, and an empty string for string format specifiers.
+
+## Examples
+
+```sh
+# print 64 as a hexadecimal number, with the starting '0x'
+$ printf '%#x' 64
+
+# prints "a0\n", ignoring everything after '\c'
+$ printf '%s%d\n\caaaa' a
+
+# prints "123400", as 'x' is an invalid number, and the missing argument for the last '%d' is treated as zero.
+$ printf '%d%d%d' 1 2 3 4 x
+```
+
+## See also
+
+* [`echo`(1)](../man1/echo.md)