Parsearg

+ examples -> parsearg/examples
+ clarified MVC components in examples/{a,a_aa}.py

+ clarified the 'todos' example:
clearly label the individual Model, View and Controller ("MVC") parts of the design

+ added two examples:
./examples/a.py the A-tree example
./examples/a_aa.py the full A-AA-tree example

+ added comprehensive example:
./examples/todos.sh

+ fixtures in conftest

+ first working version [example: tests/test_parser.py]

base$ SRC=parser/parser
base$ cd $SRC
bash$ pytest -v -s tests/test_parser.py | less

+ add parser.py
+ add tests/test_parser.py
+ add fixtures [tests/conftest.py]

+ finish test_data_structures.py
+ add parser.py