Typo, redundant string interpolation, namespaces and imports cleanup (#2068)

* Readonly, typos and redundant string interpolations

* Namespaces

* Optimize imports

* Address reviews

* but actually

* Localize missing strings

* Remove redundant vars

Content.Server/GameObjects/Components/Chemistry/SolutionContainerComponent.cs

@@ -20,7 +20,6 @@ using Robust.Shared.Prototypes;
 using Robust.Shared.Serialization;
 using Robust.Shared.Utility;
 using Robust.Shared.ViewVariables;
-using System;
 
 namespace Content.Server.GameObjects.Components.Chemistry
 {