Implement bool.real, bool.imag bool.conjugate()

There are some attributes that should be implemented for gpython.

## Expected
```python
>>> a = True
>>> a.imag
0
>>> a.real
1
>>> a.conjugate()
1
```

## Actual
```python
>>> a = True
>>> a.image
Traceback (most recent call last):
File "", line 1, in
FIXME line of source goes here
AttributeError: "'bool' has no attribute 'image'"
>>> a.real
Traceback (most recent call last):
File "", line 1, in
FIXME line of source goes here
AttributeError: "'bool' has no attribute 'real'"
>>> a.conjugate()
Traceback (most recent call last):
File "", line 1, in
FIXME line of source goes here
AttributeError: "'bool' has no attribute 'conjugate'"
```