Convert the parser module test to use PyUnit.

Lib/test/output/test_parser

-test_parser
-Expressions:
-expr: foo(1)
-expr: [1, 2, 3]
-expr: [x**3 for x in range(20)]
-expr: [x**3 for x in range(20) if x % 3]
-expr: foo(*args)
-expr: foo(*args, **kw)
-expr: foo(**kw)
-expr: foo(key=value)
-expr: foo(key=value, *args)
-expr: foo(key=value, *args, **kw)
-expr: foo(key=value, **kw)
-expr: foo(a, b, c, *args)
-expr: foo(a, b, c, *args, **kw)
-expr: foo(a, b, c, **kw)
-expr: foo + bar
-expr: lambda: 0
-expr: lambda x: 0
-expr: lambda *y: 0
-expr: lambda *y, **z: 0
-expr: lambda **z: 0
-expr: lambda x, y: 0
-expr: lambda foo=bar: 0
-expr: lambda foo=bar, spaz=nifty+spit: 0
-expr: lambda foo=bar, **z: 0
-expr: lambda foo=bar, blaz=blat+2, **z: 0
-expr: lambda foo=bar, blaz=blat+2, *y, **z: 0
-expr: lambda x, *y, **z: 0
-
-Statements:
-suite: print
-suite: print 1
-suite: print 1,
-suite: print >>fp
-suite: print >>fp, 1
-suite: print >>fp, 1,
-suite: a
-suite: a = b
-suite: a = b = c = d = e
-suite: a += b
-suite: a -= b
-suite: a *= b
-suite: a /= b
-suite: a %= b
-suite: a &= b
-suite: a |= b
-suite: a ^= b
-suite: a <<= b
-suite: a >>= b
-suite: a **= b
-suite: def f(): pass
-suite: def f(*args): pass
-suite: def f(*args, **kw): pass
-suite: def f(**kw): pass
-suite: def f(foo=bar): pass
-suite: def f(foo=bar, *args): pass
-suite: def f(foo=bar, *args, **kw): pass
-suite: def f(foo=bar, **kw): pass
-suite: def f(a, b): pass
-suite: def f(a, b, *args): pass
-suite: def f(a, b, *args, **kw): pass
-suite: def f(a, b, **kw): pass
-suite: def f(a, b, foo=bar): pass
-suite: def f(a, b, foo=bar, *args): pass
-suite: def f(a, b, foo=bar, *args, **kw): pass
-suite: def f(a, b, foo=bar, **kw): pass
-suite: from sys.path import *
-suite: from sys.path import dirname
-suite: from sys.path import dirname as my_dirname
-suite: from sys.path import dirname, basename
-suite: from sys.path import dirname as my_dirname, basename
-suite: from sys.path import dirname, basename as my_basename
-suite: import sys
-suite: import sys as system
-suite: import sys, math
-suite: import sys as system, math
-suite: import sys, math as my_math
-
-Invalid parse trees:
-
-<junk>
-caught expected exception for invalid tree
-
-print >>fp,
-caught expected exception for invalid tree
-
-a,,c
-caught expected exception for invalid tree
-
-a $= b
-caught expected exception for invalid tree