Add open_addressed_hash_table/ project dir, README.

data_structures/open_addressed_hash_table/README.md
	-Add a brief README describing the open-addressed hash table
	project's contents.
Add skeleton open_addressed_hash_table module.

data_structures/open_addressed_hash_table/open_addressed_hash_table.py
	-Declare `OpenAddressedHashTable` class, with all of the
	necessary skeleton methods.
Def __init__(), insert(), contains().

data_structures/open_addressed_hash_table/open_addressed_hash_table.py
	-Define the `OpenAddressedHashTable` constructor, as well as
	`insert()` and `contains()`.
	-Additionally define magic methods `__len__()` and `__str__()`,
	to aid in debugging.
Add class/function docstrings, rename contains().

data_structures/open_addressed_hash_table/open_addressed_hash_table.py
	-Add docstrings to `OpenAddressedHashTable` and all of its
	implemented methods.
	-Rename `contains()` to `index()`, to better reflect its
	purpose.
Rewrite index(), modify insert(), def remove().

data_structures/open_addressed_hash_table/open_addressed_hash_table.py
	-Rewrite `index()` to return either the index of the found item,
	or the first occurrence of vacant/None, such that it's
	generalized for both `insert()` and `remove()`.
	-Rewrite `insert()` accordingly.
	-Implement `remove()`.
Add unittest unit-tests.

data_structures/open_addressed_hash_table/test.py
	-Add `unittest` unit-tests for the `open_addressed_hash_table`
	module.
	-Define tests for `insert()`, `remove()`, and `index()`.
Define load_factor(), _resize().

data_structures/open_addressed_hash_table/open_addressed_hash_table.py
	-Define and add docstrings to `load_factor()` and `_resize()`.
	-Add mention of dynamic-resizing using `_resize()` to
	`insert()`.
Add unit-test for _resize().

data_structures/open_addressed_hash_table/test.py
	-Define `test_resize()`, which tests `_resize()`.
Add content to README.

data_structures/open_addressed_hash_table/README.md
	-Add code demonstrating sample usage.
	-Provide instructions on running the module's unit-tests.
Merge branch 'data_structures/open_addressed_hash_table' into develop

data_structures/open_addressed_hash_table/
	-Implement a dynamically resizing, open-addressed hash table.