Adopt generator-exist, add tests

I'd been reviewing https://github.com/eXist-db/exist-markdown/pull/14 when I created the branch....

See https://github.com/eXist-db/templating/pull/12.

Implicitly demonstrated with test.md and the operations of the library.

and delete 'HTML blocks' test which was really a code block test

In `declare %annotation function`, the annotations are indented but not the `declare` or `functi...

Added `%test:pending` for failing tests.

I think I added all the necessary tests. The inline HTML doesn't transform the <mark> element, a...

- adapted from https://github.com/eXist-db/templating
- note that gulp-exist "^4.0.0" (which dow...

The first few examples from test.md

- paragraph delimiters
- inline-code
- inline-code-backtick...

- generator-exist provides common scaffolding and integrates practices for testing and CI
- use ...

Fix misinterpretation of inline strong as list

for clarity's sake

Toward a fix for markdown

See https://www.w3.org/TR/xpath-functions-31/#flags

(at line beginning)

- Adopt full semver 2.0 version number
- Backfill release notes for 0.6

Remove shared-resources dependency

Remove erroneous prepare step

There is no `pre-install.xql`!

Fix reserved ns prefix

… and ensure expath-pkg.xml is removed from the repo; ignoring it wasn’t enough

Closes #2