Fix documentation build (#44)

Author: tjjarvinen

docs/make.jl

@@ -4,7 +4,7 @@ using PotentialCalculation, PotentialCalculation.psi4
 makedocs(sitename="PotentialCalculation.jl",
          pages=["Home" => "index.md",
                 "Install" => "install.md",
-                "Building Molecules" => "structure_creation.md"
+                "Building Molecules" => "structure_creation.md",
                 "Usage" => "use.md",
                 "References" => "reference.md"]