Creates directory including parent directories, if necessary. Then changes
current working directory to it.
-: **mdiff()**
-Diffs the two arguments recursively and writes the
-output (unified format) to a timestamped file.
-
-: **memusage()**
-Prints the summarized memory usage in bytes.
-
: **mggogle()**
Searches Google Groups for a USENET message-ID.
Lists the contents of a (compressed) archive with the appropriate programs.
The choice is made along the filename extension.
-: **shtar()**
-Lists the content of a gzipped tar archive in default pager.
-
-: **shzip()**
-Shows the content of a zip archive in default pager.
-
: **simple-extract()**
Tries to uncompress/unpack given files with the appropriate programs. If an URI
starting with https, http or ftp is provided simple-extract tries to download