Class SQLTABLE

       object --+            
                |            
html.XmlComponent --+        
                    |        
             html.DIV --+    
                        |    
               html.TABLE --+
                            |
                           SQLTABLE

given a Rows object, as returned by a db().select(), generates
an html table with the rows.

optional arguments:

:param linkto: URL (or lambda to generate a URL) to edit individual records
:param upload: URL to download uploaded files
:param orderby: Add an orderby link to column headers.
:param headers: dictionary of headers to headers redefinions
                headers can also be a string to gerenare the headers from data
                for now only headers="fieldname:capitalize",
                headers="labels" and headers=None are supported
:param truncate: length at which to truncate text in table cells.
    Defaults to 16 characters.
:param columns: a list or dict contaning the names of the columns to be shown
    Defaults to all

Optional names attributes for passed to the <table> tag

The keys of headers and columns must be of the form "tablename.fieldname"

Simple linkto example::

    rows = db.select(db.sometable.ALL)
    table = SQLTABLE(rows, linkto='someurl')

This will link rows[id] to .../sometable/value_of_id


More advanced linkto example::

    def mylink(field, type, ref):
        return URL(r=request, args=[field])

    rows = db.select(db.sometable.ALL)
    table = SQLTABLE(rows, linkto=mylink)

This will link rows[id] to
    current_app/current_controlle/current_function/value_of_id
    
New Implements: 24 June 2011:
-----------------------------

:param selectid: The id you want to select
:param renderstyle: Boolean render the style with the table

:param extracolums = [{'label':A('Extra',_href='#'),
                'class': '', #class name of the header
                'width':'', #width in pixels or %
                'content':lambda row, rc: A('Edit',_href='edit/%s'%row.id),                     
                'selected': False #agregate class selected to this column
                }]
                
                
:param headers = {'table.id':{'label':'Id',
                       'class':'', #class name of the header
                       'width':'', #width in pixels or %
                       'truncate': 16, #truncate the content to...
                       'selected': False #agregate class selected to this column
                       }, 
           'table.myfield':{'label':'My field',
                            'class':'', #class name of the header
                            'width':'', #width in pixels or %
                            'truncate': 16, #truncate the content to...
                            'selected': False #agregate class selected to this column
                            },
           }
           
table = SQLTABLE(rows, headers=headers, extracolums=extracolums)