A template for Mathematica packages.

MyPackage.m

BeginPackage["MyPackage`"];

Unprotect["MyPackage`*"];
ClearAll["MyPackage`*", "MyPackage`Private`*"];

(******************************************************************************)

MyAdd::usage = "MyAdd[a,b] returns a+b.";

Begin["`Private`"];

(******************************************************************************)

MyAdd[a_, b_] := a + b;

(******************************************************************************)

Scan[SetAttributes[#, {Protected, ReadProtected}]&,
     Select[Symbol /@ Names["MyPackage`*"], Head[#] === Symbol &]];

End[];
EndPackage[];

:%s/MyPackage/NewPackage/g