tests.py: Add interpreter and module info
tests.py: Add interpreter and module info

There can be several Python interpreters on the system (especially on
Windows), and the modules can be in various places (especially in a
development system).Just show this info.

For example, the following is included in tests.py.log after "make check":

Running by: /usr/bin/python
Running /usr/local/src/link-grammar-devel/pytests/bindings/python-examples/tests.py in: /tmp/link-grammar/pytests/bindings/python-examples
PYTHONPATH=/usr/local/src/link-grammar-devel/pytests/bindings/python-examples/../python:../python:../python/.libs
srcdir=/usr/local/src/link-grammar-devel/pytests/bindings/python-examples
LINK_GRAMMAR_DATA=/usr/local/src/link-grammar-devel/pytests/bindings/python-examples/../../data
Using <module 'linkgrammar' from '/usr/local/src/link-grammar-devel/pytests/bindings/python/linkgrammar.pyc'>
Using <module '_clinkgrammar' from '/tmp/link-grammar/pytests/bindings/python/.libs/_clinkgrammar.so'>

And on a manual run of tests.py after install:

Running by: /usr/bin/python
Running tests.py in: /usr/local/src/link-grammar-devel/pytests/bindings/python-examples
PYTHONPATH=/usr/local/lib/python2.7/site-packages
srcdir=None
LINK_GRAMMAR_DATA=../../data
Using <module 'linkgrammar' from '/usr/local/lib/python2.7/site-packages/linkgrammar/__init__.pyc'> version 5.3.8
Using <module '_clinkgrammar' from '/usr/local/lib/python2.7/site-packages/linkgrammar/_clinkgrammar.so'>

opencog/link-grammar,linas/link-grammar,linas/link-grammar,ampli/link-grammar,linas/link-grammar,opencog/link-grammar,ampli/link-grammar,opencog/link-grammar,ampli/link-grammar,linas/link-grammar,linas/link-grammar,linas/link-grammar,opencog/link-grammar,ampli/link-grammar,linas/link-grammar,opencog/link-grammar,ampli/link-grammar,ampli/link-grammar,linas/link-grammar,opencog/link-grammar,opencog/link-grammar,ampli/link-grammar,ampli/link-grammar,opencog/link-grammar,opencog/link-grammar,linas/link-grammar,ampli/link-grammar