Fix tutorial demo (#269)

* closes #266

* fixed BibTeX entry and removed unnecessary temproary file

Author: simsong

docs/source/demo.py

@@ -0,0 +1,53 @@
+import logging
+import logging.config
+import io
+
+logger = logging.getLogger(__name__)
+
+logging.config.dictConfig({
+    'version': 1,
+    'disable_existing_loggers': False,
+    'formatters': {
+        'standard': {
+            'format': '%(asctime)s [%(levelname)s] %(name)s %(funcName)s:%(lineno)d: %(message)s'
+        },
+    },
+    'handlers': {
+        'default': {
+            'level':'DEBUG',
+            'formatter': 'standard',
+            'class':'logging.StreamHandler',
+        },
+    },
+    'loggers': {
+        '': {
+            'handlers': ['default'],
+            'level': 'DEBUG',
+            'formatter': 'standard',
+            'propagate': True
+        }
+    }
+})
+
+
+if __name__ == '__main__':
+    bibtex_source = """@ARTICLE{Cesar2013,
+      author = {Jean César},
+      title = {An amazing title},
+      year = {2013},
+      month = {1},
+      volume = {12},
+      pages = {12--23},
+      journal = {Nice Journal},
+      abstract = {This is an abstract. This line should be long enough to test
+    	 multilines...},
+      comments = {A comment},
+      keywords = {keyword1, keyword2},
+    }
+    """
+
+    from bibtexparser.bparser import BibTexParser
+
+    with io.StringIO(bibtex_source) as f:
+        bp = BibTexParser(f.read())
+        print(bp.get_entry_list())