Python: document writer.Stream

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Python: document writer.Writer

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Python: doc: reader: ``int`` -> :class:`int`

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Python: add reader.IntegerFieldDeclaration.size

The CTF specifications use "size" rather than "length"
for an integer type, and on the Python side,
babeltrace.writer.IntegerFieldDeclaration.size is used.

babeltrace.reader.IntegerFieldDeclaration.length is
kept here for backward compatibility reasons.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Python: writer.IntegerBase: remove redundant prefixes

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Python: add Sphinx doc project

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>