Merge pull request #552 from microsoft/personal/duburson/convert-api-docs

Initial documentation release FHIR Converter API *Preview*

- Update main readme for new updated container based convert.
- Readme updated with previous version section, which directs to prior versions.
- Create concept documents for resource id generation and validation.
- Add example using built in date filter to Filter and Tags documentation.
- Remove no longer relevant TempleteManagementCLI.md from main.

Author: dustinburson

README.md

@@ -1,7 +1,5 @@
 # Filters and Tags
 
-⚠ **This document applies to the Liquid engine. Follow [this](https://github.com/microsoft/FHIR-Converter/tree/handlebars) link for the documentation of Handlebars engine.**
-
 ## Filters
 
 By default, Liquid provides a set of [standard filters](https://github.com/Shopify/liquid/wiki/Liquid-for-Designers#standard-filters) to assist template creation.
@@ -59,6 +57,7 @@ If these filters do not meet your needs, you can also write your own filters.
 | format_as_date_time | Converts valid HL7v2 and C-CDA datetime to a valid FHIR datetime format. The input datetime format is datetime or partial datetime without hyphens: YYYY[MM[DD[HH[MM[SS[.S[S[S[S]]]]]]]]][+/-ZZZZ]. For example, the input 20040629175400000 will have the output 2004-06-29T17:54:00.000Z. Provides parameters to handle different time zones: preserve, utc, local. The default method is preserve. | `{{ PID.29.Value \| format_as_date_time: 'utc' }}` |
 | now | Provides the current time in a specific format. The default format is yyyy-MM-ddTHH:mm:ss.FFFZ. | `{{ '' \| now: 'dddd, dd MMMM yyyy HH:mm:ss' }}` |
 | add_seconds | Adds double seconds on a valid [FHIR datetime](http://hl7.org/fhir/R4/datatypes.html) (e.g.2021-01-01T00:00:00Z). Provides parameters to handle different time zones: preserve, utc, local. The default method is preserve. | `{{ "2021-01-01T00:00:00Z" \| add_seconds:100.1, 'utc' }}` |
+| date | This is the standard [Liquid date filter](https://github.com/Shopify/liquid/wiki/Liquid-for-Designers#standard-filters).  In the underlying DotLiquid implementation, .NET date formats are used ([standard](https://learn.microsoft.com/en-us/dotnet/standard/base-types/standard-date-and-time-format-strings) & [custom](https://learn.microsoft.com/en-us/dotnet/standard/base-types/custom-date-and-time-format-strings)). | `{{ msg.date \| date: "yyyy-MM-ddTHH:mm:ss.fff" }}` |
 
 DateTime filters usage examples: