Signed-off-by: Steve Swor <sworisbreathing@users.noreply.github.com>

Add limit parameter to image search endpoint

Fix images low-level documentation examples

Fix containers low-level documentation examples

I realize that low-level documentation has outdated examples, so I
created issue #2800 to fix that

Signed-off-by: Felipe Ruhland <felipe.ruhland@gmail.com>

I realize that the documentation of low-level `images` was outdated when
answering issue #2798

The issue can reproduce it with a simple test:

```py
In [1]: import docker
In [2]: client = docker.from_env()
In [3]: client.pull
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-3-d0931943ca5d> in <module>
----> 1 client.pull

~/docker-py/docker/client.py in __getattr__(self, name)
    219                      "object APIClient. See the low-level API section of the "
    220                      "documentation for more details.")
--> 221         raise AttributeError(' '.join(s))
    222
    223

AttributeError: 'DockerClient' object has no attribute 'pull' In Docker SDK for Python 2.0, this method is now on the object APIClient. See the low-level API section of the documentation for more details.

In [4]: client.push
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-4-f7d5b860a184> in <module>
----> 1 client.push

~/docker-py/docker/client.py in __getattr__(self, name)
    219                      "object APIClient. See the low-level API section of the "
    220                      "documentation for more details.")
--> 221         raise AttributeError(' '.join(s))
    222
    223

AttributeError: 'DockerClient' object has no attribute 'push' In Docker SDK for Python 2.0, this method is now on the object APIClient. See the low-level API section of the documentation for more details.

In [5]: client.tag
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-5-043bdfd088ca> in <module>
----> 1 client.tag

~/docker-py/docker/client.py in __getattr__(self, name)
    219                      "object APIClient. See the low-level API section of the "
    220                      "documentation for more details.")
--> 221         raise AttributeError(' '.join(s))
    222
    223

AttributeError: 'DockerClient' object has no attribute 'tag' In Docker SDK for Python 2.0, this method is now on the object APIClient. See the low-level API section of the documentation for more details.

In [6]: client.get_image
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-6-477c12713276> in <module>
----> 1 client.get_image

~/docker-py/docker/client.py in __getattr__(self, name)
    219                      "object APIClient. See the low-level API section of the "
    220                      "documentation for more details.")
--> 221         raise AttributeError(' '.join(s))
    222
    223

AttributeError: 'DockerClient' object has no attribute 'get_image' In Docker SDK for Python 2.0, this method is now on the object APIClient. See the low-level API section of the documentation for more details.

In [7]: client.api.get_image
Out[7]: <bound method ImageApiMixin.get_image of <docker.api.client.APIClient object at 0x7fad6a2037c0>>

In [8]: client.api.tag
Out[8]: <bound method ImageApiMixin.tag of <docker.api.client.APIClient object at 0x7fad6a2037c0>>

In [9]: client.api.pull
Out[9]: <bound method ImageApiMixin.pull of <docker.api.client.APIClient object at 0x7fad6a2037c0>>

In [10]: client.api.push
Out[10]: <bound method ImageApiMixin.push of <docker.api.client.APIClient object at 0x7fad6a2037c0>>
```

Signed-off-by: Felipe Ruhland <felipe.ruhland@gmail.com>

Upgrade cryptography library to version 3.4.7

Dependabot opened a pull request
93bcc0497d8302aa2d78bd7ef756fc2ff3fd0912 to upgrade cryptography from
2.3 to 3.2.

However, only `requirements.txt` was updated.
The extra requirements were kept outdated.

This commit was made to update the library to the last version.

Fix #2791

Signed-off-by: Felipe Ruhland <felipe.ruhland@gmail.com>

Fix continuous integration status badged

Make python 3.6 the minimum version