[DOXIA-712] Add validation capability to Sink API

**[Konrad Windszus](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=kwin)** opened **[DOXIA-712](https://issues.apache.org/jira/browse/DOXIA-712?redirect=false)** and commented

The Sink API comes with several limitations with regards to valid order of events/method calls and valid parametrization. Those are documented in the javadoc of the Sink interface but are complex to follow. This includes

- certain start events need to be followed by an according end event
- `sectionTitle(int,SinkEventAttributes)` needs to be directly preceded by `section(int,SinkEventAttributes)` with the same first argument.
- certain rules for sequence of events for `table`, `list` (numbered, non-numbered and definition) and `figure`
- validation of certain common parameters like `level` or `SinkEventAttributes` for valid values

As we encourage the direct usage of the Sink API for report mojos there should be a way for mojo authors to quickly crosscheck whether they used the Sink API in a correct way.

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**Issue Links:**
- [DOXIA-711](https://issues.apache.org/jira/browse/DOXIA-711) Introduce SinkWrapper with factory
(_**"is blocked by"**_)
- [DOXIA-699](https://issues.apache.org/jira/browse/DOXIA-699) Xhtml5Parser may emit sectionX() without sectionX_() when using both \ and \

Start by reading the Sink interface Javadoc and the linked DOXIA-711 issue about introducing SinkWrapper with a factory. The work is done when Sink API event ordering and parameter rules can be checked through the proposed validation capability.

Written by the indexing model from the issue text.