Added new filters for templates

[skalavala]

Description:

Added base64 encode, base64 decode and ordinal filters for templates.

Related issue (if applicable): fixes #

Pull request in home-assistant.io with documentation (if applicable): home-assistant/home-assistant.io#<home-assistant.io PR number goes here>

Example entry for configuration.yaml (if applicable):

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• New dependencies have been added to the REQUIREMENTS variable (example).
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• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.
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If the code does not interact with devices:

• Tests have been added to verify that the new code works.

[balloob]

use case?

[skalavala]

use case?

The ordinal filter is used to display properly formatted text in the UI, as well as for TTS. I can now announce that it is "65th birthday" instead of instead of "65 years old".

The base64_encode and decode are used for the curl command that expects header variables in base64 encoded format. Without this, there is no way to pass base64 encoded variables using templates. 😄

[balloob]

We don't have a curl command?

[skalavala]

We don't have a curl command?

We don't have curl command. We have shell_command and rest_command that people normally use.

[balloob]

I don't find that a good reason to add base64 to our templating engine. People can have their shell command call a script that does the encoding? I'm a bit scared of turning our template engine into a data preparation tool for all possible CLIs out there.

[pvizeli]

Base64 could be fine, because it's hard to do this with shell scripts and make rest_command more powerful but the other one for 65th is strange.

[skalavala]

Base64 could be fine, because it's hard to do this with shell scripts and make rest_command more powerful but the other one for 65th is strange.

I added the ordinal filter only because we get number of people in the forum asking for it for their tts or for display in the UI. We can remove that if we don't want it support that.

However, addition of base64 en/decoding would be very useful and currently there is no clean way of implementing that effectively when using the services like rest_command or shell_command.

[balloob]

Can be merged when docs added