Loads an acclaim skeleton format from a file stream.

def read_skel(self, fid):
        """Loads an acclaim skeleton format from a file stream."""
        lin = self.read_line(fid)
        while lin:
            if lin[0]==':':
                if lin[1:]== 'name':
                    lin = self.read_line(fid)
                    self.name = lin
                elif lin[1:]=='units':
                    lin = self.read_units(fid)
                elif lin[1:]=='documentation':
                    lin = self.read_documentation(fid)
                elif lin[1:]=='root':
                    lin = self.read_root(fid)
                elif lin[1:]=='bonedata':
                    lin = self.read_bonedata(fid)
                elif lin[1:]=='hierarchy':
                    lin = self.read_hierarchy(fid)
                elif lin[1:8]=='version':
                    lin = self.read_line(fid)
                    continue
                else: 
                    if not lin:
                        self.finalize()
                        return
                    lin = self.read_line(fid)
            else:
                raise ValueError('Unrecognised file format')
            self.finalize()