Generate HTML documentation using MkDocs (WIP)

MkDocs is a static site generator geared towards building project documentation.
Documentation source files are written in Markdown, and configured with a single YAML file.

 * http://www.mkdocs.org/
 * http://www.mkdocs.org/user-guide/configuration/

Ref. #312

* remove pandoc-generated HTML documentation
* move markdown doc to doc/md/,
* mkdocs.yml:
  * generate HTML doc in doc/html
  * add pages TOC/ordering
  * use index.md as index page
* Makefile: remove execute permissions from generated files
* Makefile: rewrite htmlpages GFM to markdown conversion using sed:
   awk expression aslo matched '][' which causes invalid output on complex links with images or code blocks
* Add mkdocs.yml to .gitattributes, exclude this file from release archives
* Makefile: rename: htmldoc -> doc_html target
* run make doc: pull latest markdown documentation from wiki
* run make htmlpages: update html documentation

1 files changed, 26 insertions, 0 deletions

diff --git a/doc/md/RSS-feeds.md b/doc/md/RSS-feeds.md
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index 00000000..9d718172
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+++ b/doc/md/RSS-feeds.md
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+### Feeds options
+
+Feeds are available in ATOM with `?do=atom` and RSS with `do=RSS`.
+
+Options:
+- You can use `permalinks` in the feed URL to get permalink to Shaares instead of direct link to shaared URL.
+    - E.G. `https://my.shaarli.domain/?do=atom&permalinks`.
+- You can use `nb` parameter in the feed URL to specify the number of Shaares you want in a feed (default if not specified: `50`). The keyword `all` is available if you want everything.
+    - `https://my.shaarli.domain/?do=atom&permalinks&nb=42`
+    - `https://my.shaarli.domain/?do=atom&permalinks&nb=all`
+
+### RSS Feeds or Picture Wall for a specific search/tag
+
+It is possible to filter RSS/ATOM feeds and Picture Wall on a Shaarli to **only display results of a specific search, or for a specific tag**.
+
+For example, if you want to subscribe only to links tagged `photography`:
+- Go to the desired Shaarli instance.
+- Search for the `photography` tag in the _Filter by tag_ box. Links tagged `photography` are displayed.
+- Click on the `RSS Feed` button.
+- You are presented with an RSS feed showing only these links. Subscribe to it to receive only updates with this tag.
+- The same method **also works for a full-text search** (_Search_ box) **and for the Picture Wall** (want to only see pictures about `nature`?)
+- You can also build the URLs manually: 
+    - `https://my.shaarli.domain/?do=rss&searchtags=nature`
+    - `https://my.shaarli.domain/links/?do=picwall&searchterm=poney`
+
+![](images/rss-filter-1.png) ![](images/rss-filter-2.png)