Master (#6)

* Prep for 2.1.3 (RomelTorres#178)

* Fixing pypi badge

* Fixing typo on README

* Use ==/!= to compare str, bytes, and int literals

Identity is not the same thing as equality in Python so use ==/!= to compare str, bytes, and int literals. In Python >= 3.8, these instances will raise SyntaxWarnings so it is best to fix them now. https://docs.python.org/3.8/whatsnew/3.8.html#porting-to-python-3-8

$ python
```
>>> pandas = "panda"
>>> pandas += "s"
>>> pandas == "pandas"
True
>>> pandas is "pandas"
False
```

* added rapidapi key integration

Co-authored-by: Igor Tavares <igorborgest@gmail.com>
Co-authored-by: Christian Clauss <cclauss@me.com>
Co-authored-by: Patrick Collins <patrick.collins@alphavantage.co>

* Prep for 2.2.0 (RomelTorres#210)

* added rapidapi key integration

* prep for 2.1.3

* Removing get_batch_stock_quotes method (RomelTorres#189)

* Removing get_batch_stock_quotes method

Remove get_batch_stock_quotes method, resolving issue RomelTorres#184.

* remove tests for get_batch_stock_quotes

* Delete mock_batch_quotes

Was only used for the tests removed in the previous commits, which made this file dead weight.

* Add asyncio support for all components (RomelTorres#191)

* Add asyncio support for all components

In order to minimize the copy-paste between the async and sync
implementations, all of the non-base components are sym-linked to their
sync counterparts.  Since these import `AlphaVantage` locally, they
automatically pick up the async version, which is really nifty!

There was some refactoring in `SectorPerformance` to make the re-use
possible.

The async verison of AlphaVantage tries to re-use as much as possible
from the sync version.  The main differences are:
* a new `session` for the HTTP calls
* a new `close()` function which should be called when you're done
* `proxy` is a string instead of a dict

Using it:
```python
import asyncio
from alpha_vantage.async_support.timeseries import TimeSeries

async def get_data():
    ts = TimeSeries(key='YOUR_API_KEY')
    data, meta_data = await ts.get_intraday('GOOGL')
    await ts.close()

loop = asyncio.get_event_loop()
loop.run_until_complete(get_data())
loop.close()
```

* Add asyncio packages to setup.py

* Issue RomelTorres#206: Add 'time_period' argument to 'get_bbands()' documentation. (RomelTorres#207)

* Fixes small documentation bugs (RomelTorres#208)

* fixed fx documentation

* fixed pypi badge for documentation

* prep for 2.2.0 (RomelTorres#209)

* fixed fx documentation

* fixed pypi badge for documentation

* prep for 2.2.0

* small documentaiton change for 2.2.0

Co-authored-by: Aaron Sanders <sandersaarond@gmail.com>
Co-authored-by: Jon Cinque <jon.cinque@gmail.com>
Co-authored-by: Peter Anderson <BWPanda@users.noreply.github.com>