Command: alias/unalias - handling shortcuts for commands

Description:
	The 'alias' command is to make shortcuts (aliases) for all kinds
	of commands usable in Nemesis.

Syntax:
	alias			shows the list of your current shortcuts.
	alias <name>		shows the content of alias <name>.
	alias <name> <cmd>	add or replace <name> as shortcut for <cmd>.
	alias <name> "<cmd>"	add or replace <name> as shortcut for <cmd>
				which may contain leading or ending <spaces>.
	unalias <name>		removes the alias <name>.

Examples:
	alias g giggle		shortcuts 'giggle' by 'g' - results to:
	g ina			causes you to giggle inanely.

	alias gr "grin de"	shortcuts 'grin de' by 'gr' - results to:
	gr			causes you to grin deadly.
	gr m			causes you to grin demonically.
	gr v			causes you to grin devilishly.

Note:
	'alias <name> <cmd>' is the same as 'alias <name> "<cmd> "'.

	'alias' may itself be shortcutted by  'a', 'al', 'ali' or 'alia'.

	For further abbreviations see 'help abbreviations'.

	The 'alias' system is part the  S h e l l  coded by Mangar the Dark.
	More about Mangar see https://nemesis.de/lpc/bin/finger/mangar or
	try 'whois mangar'.
	Any occurring errors should be reported to admin (see 'help admin')
	or via 'bug me shell <problem>' (see 'help bug') or 'idea me shell
	<idea>' (see 'help idea') etc.

See also: helpdir/shell, helpdir/do, helpdir/history, helpdir/abbreviations, helpdir/admin, helpdir/bug, helpdir/idea