fixed similarity tutorial and started changing syntax of files

Author: johndoe12312

docs/generated-html/book-gephi-tutorials-en.html

@@ -474,7 +474,7 @@ <h1>Creating a network from a table of cooccurring items</h1>
 <div id="preamble">
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-<p>last modified: 2017-10-06</p>
+<p>last modified: 2019-07-12</p>
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 <div class="imageblock text-center">
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@@ -822,7 +822,7 @@ <h2 id="_the_end">The end</h2>
 <div id="footer">
 <div id="footer-text">
 Version 1.0<br>
-Last updated 2017-10-06 11:56:46 +0200
+Last updated 2019-07-12 19:05:35 +0200
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