func Term(src interface{}) (term.Term, error) {
	r, err := NewTermReader(src)
	if err != nil {
		return nil, err
	}
	return r.Next()
}
Term reads a single term from a term source.  A term source can
be any of the following:

* type that implements io.Reader
* string

Reading a term may consume more content from the source than is strictly
necessary.
package read
import (
	"fmt"
	"io"
	"strings"
	"github.com/mndrix/golog/lex"
	"github.com/mndrix/golog/term"
)
var NoMoreTerms = fmt.Errorf("No more terms available")
type specifier int  
const (
	fx specifier = iota
	fy
	xfx
	xfy
	yfx
	xf
	yf
)
type priority int  