Fix description in nuspec

Author: kristiandupont

NuGet/NuGet.Library/Realm.nuspec

@@ -11,7 +11,7 @@
     <projectUrl>http://github.com/realm/realm-dotnet</projectUrl>
     <iconUrl>http://realm.io/img/favicon-32x32.png</iconUrl>
     <requireLicenseAcceptance>false</requireLicenseAcceptance>
-    <description>Realm is a mobile database: an alternative to SQLite and key-value stores (private beta)</description>
+    <description>Realm is a mobile database: a replacement for SQLite & ORMs</description>
     <summary />
     <language>en-US</language>
     <tags>Realm database db persistence sqlite</tags>