Add PropertyWebBuilder

This is a real estate website builder.  Doesn't seem to fit in any of the defined categories so added it to "Misc/Other"

README.md

@@ -779,6 +779,7 @@ See also <https://en.wikipedia.org/wiki/List_of_streaming_media_systems>, <https
   * [Musical Artifacts](https://musical-artifacts.com/) - Helping to catalog, preserve and free the artifacts you need to produce music. ([Source Code](https://github.com/lfzawacki/musical-artifacts)) `MIT` `Ruby`
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   * [Notica](https://notica.us) - Lets you send browser notifications from your terminal to your desktop or phone. No installation or registration is required. ([Source Code](https://github.com/tannercollin/Notica)) `MIT` `Nodejs`
+  * [PropertyWebBuilder](http://propertywebbuilder.com) - The ultimate Ruby on Rails engine for creating real estate websites. ([Demo](https://propertywebbuilder.herokuapp.com), [Source Code](https://github.com/etewiah/property_web_builder)) `MIT` `Ruby`
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   * [Trello Burndown](https://github.com/swordbeta/trello-burndown) `⚠` - An easy to use SCRUM burndown chart for Trello boards. `MIT` `Go/Docker`
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