Add SiteGround Hosting to the list of adopters (piskvorky#1314)

* Fix issue 511 with passing 'sentences' as parameter to doc2vec, causing a weird behaviour with word2vec

* Added SiteGround Hosting to adopters

* Changes to more accurate description for SiteGround usage of gensim

* Fixed typo in adopters record for SiteGround

README.md

@@ -135,6 +135,7 @@ Adopters
 | Stillwater Supercomputing     | <img src="http://www.stillwater-sc.com/img/stillwater-logo.png" width="100"> | [stillwater-sc.com](http://www.stillwater-sc.com/)                                  | Document comprehension and association with word2vec |
 | Channel 4     | <img src="http://www.channel4.com/static/info/images/lib/c4logo_2015_info_corporate.jpg" width="100"> | [channel4.com](http://www.channel4.com/)                                  | Recommendation engine |
 | Amazon     |  <img src="http://g-ec2.images-amazon.com/images/G/01/social/api-share/amazon_logo_500500._V323939215_.png" width="100"> | [amazon.com](http://www.amazon.com/)                                  |  Document similarity|
+| SiteGround Hosting     |  <img src="https://www.siteground.com/img/knox/logos/siteground.png" width="100"> | [siteground.com](https://www.siteground.com/)                                  | An ensemble search engine which uses different embeddings models and similarities, including word2vec, WMD, and LDA. |
 
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