Mkdocs Ezlinks Plugin Versions Save

This is a bugfix release.

Issues addressed:

• GH issue #35, Links between deeply nested subfolders fails. Dev @Mara-Li reported an issue with wikilinks between deeply nested subfolders failing due to an incorrectly rendered relative link to the file.

• An unreported Windows usage issue It's possible this bug existed for quite some time. Basically, on Windows, there was disagreement between the path separators used at different points in the file mapping and searching process. This unifies it to store and search for paths only with the / delimiter instead of the OS defined separator.

Adds support for Reference Link specification links. For example, [foo]: /bar "Foo Bar".

This is a bugfix release.

Issues addressed:

• GH issue #25, Absolute links not using http:// or https:// are treated as relative. Dev @robbcrg (thanks!) reported that links with protocol schemes other than those two should also be treated as absolute links. The regex will exclude any link from a conformant protocol scheme from being converted using EzLinks.

• GH Issue #27, Dictionary file cache is not being leveraged. An inverted comparison led to the fast file cache lookup never really being exercised. Now, if a filename is unique, it will find it in the fast file cache first, saving a more expensive full trie lookup.

This is a bugfix release. The prior release switched from a dictionary lookup to a prefix trie lookup strategy, which allowed for better disambiguation between links, but is more expensive. The bug was that, even if a link was direct, it would trigger a full trie search. Now, direct links are checked and returned directly if the file exists.

Additionally, a slight performance improvement was made where, in the case that a filename is unique to the entire site, it will rely on a fast dictionary lookup instead of a trie lookup.

Implement auto-disambiguation and bugfix

* This fixes a bug in the previous search strategy that missed
  allowing for local relative links (something like index.md
  referring to about.md in the same subdirectory).

* It also adds a bit further auto-disambiguation. By this,
  I mean it will attempt to find the _closest_ match in proximity
  (with respect to the folder hierarchy). For instance,
  if this is the layout:

  ```
  + guide/
    + test.md
    + getting_started/
        + index.md
  + tutorials/
    - test.md
    + getting_started/
       + index.md
    + more_advanced/
       + index.md
  ```
  If you placed a link inside `guide/getting_started/index.md`
  such as `[Test](test)`, the resulting link has ambiguity, but
  in the default case, the `guide/test.md` file is _closer_ than
  the `tutorials/test.md`, therefore, it will select that file.

  You can still further disambiguate the link if desired, but
  this provides a bit more sane defaults.

Adds support for EzLink 'path-component' based disambiguation

This feature switches from using a dictionary to a prefix trie, caching the files in reverse order (path wise), which allows for:

+ folder1/
     - index.md
+ folder2/
     - index.md

You can now link to folder1/index.md and folder2/index.md, or folder1/index and folder2/index. This allows disambiguating duplicate filenames from separate unique paths.

This works across all link types supported by EzLinks

Fixes an issue where multiple md links on the same line are not scanned correctly, leading to broken links.

Fixes compatibility with earlier Python versions (tested against 3.6).

Contains a few bug fixes:

• Do not scan external links with an http:// or https:// prefix, which will prevent properly formatted external links from emitting a warning for a missing link target.

• Includes an init.py for the mkdocs_ezlinks_plugin/scanners module, which then is included into the distribution.

• Also downgrades some prior warnings to debug level, as most of the messages trigger existing mkdocs warnings (such as broken link warnings, etc.)

• Messages are now automatically filtered based on the '--quiet' and '--verbose' mkdocs flags.

• Update Configuration Options in README.md

Contains a significant refactor, to increase maintainability. Since it is still an alpha release, I am releasing this even though there should be no major functionality difference from a user perspective. I simply want to keep things in sync between source and release.