Perl Quiz-of-the-Week #4

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Two words are said to be 'anagrams' if the letters of one word can be
rearranged to form the other word.  For example, in English, 'ascot'
and 'tacos' are anagrams; so are 'tacos' and 'coats'.  A set of words
that are all anagrams of one another is an 'anagram set'.  For
example,

        ascot coast coats tacos

is an anagram set.

Letter case doesn't matter, so, for example, 'liberating' and
'Gilbertian' are considered to be anagrams.  

Write a program, 'make_anagrams', which reads in a list of words, one
per line, and finds all the anagrams in the the word list.  It should
output an anagram dictionary, as follows:

* 'Words' that contain digits or punctuational characters should be
  discarded.

* Anagram sets that contain only one word should be omitted from the
  output.

* If an anagram set contains two words, say 'halls' and 'shall', the
  output should contain two lines:

        halls shall
        shall halls

* If an anagram set contains more than two words, the entire set
  should be listed under the alphabetically first word; the others
  should cross-reference it.  For example:

        headskin nakedish sinkhead
        nakedish (See 'headskin')
        sinkhead (See 'headskin')

* The output lines should be in alphabetic order.

For example, if the input was

        5th
        ascot
        ate
        carrot
        coast
        coats
        cots
        Dorian
        eat
        halls
        headskin
        inroad
        nakedish
        ordain
        Ronald's
        shall
        sinkhead
        tacos
        tea

then the output should be:

        Dorian inroad ordain
        ascot coast coats tacos
        ate eat tea        
        coast (See 'ascot')
        coats (See 'ascot')
        eat (See 'ate')
        halls shall
        headskin nakedish sinkhead
        inroad (See 'Dorian')
        nakedish (See 'headskin')
        ordain (See 'Dorian')
        shall halls
        sinkhead (See 'headskin')
        tacos (See 'ascot')
        tea (See 'ate')
        
If you need a sample input, you may obtain English word lists from 
        http://perl.plover.com/qotw/words/

If you prefer to do this quiz in a language other than English, please
substitute whatever conventions are appropriate for that language.