Add Acra, database encryption & SQL prevention

https://github.com/cossacklabs/acra

README.md

@@ -501,6 +501,7 @@ If you enjoy this awesome list and would like to support it, check out my [Patre
 ### Preventing
 
 - [js-xss](https://github.com/leizongmin/js-xss) - Sanitize untrusted HTML (to prevent XSS) with a configuration specified by a Whitelist by [@leizongmin](https://github.com/leizongmin).
+- [Acra](https://github.com/cossacklabs/acra) - Client-side encryption engine for SQL databases, with strong selective encryption, SQL injections prevention and intrusion detection by [@cossacklabs](https://www.cossacklabs.com/).
 
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 ### Proxy