cleanup duplicate code on group Element creation  (not a bug)

I found that some code was duplicated when creating group Elements.  More specifically, when creating a &lt;g&gt; Snap Element, code first calls make("g",...).  
```javascript
      proto.group = proto.g = function (first) {
          var el = make("g", this.node);
          el.add = add2group;
          for (var method in proto) if (proto[has](method)) {
              el[method] = proto[method];
          }
```
make() calls wrap() ...
```javascript
  function make(name, parent) {
      var res = $(name);
      parent.appendChild(res);
      var el = wrap(res);
```
which calls new Element()
```javascript
  function wrap(dom) {
    :   :   :   :
      return new Element(dom);
```
which itself has special code for &lt;g&gt; Element creation.
```javascript
  function Element(el) {
    :   :   :   :
      this.type = el.tagName;
    :   :   :   :
      if (this.type == "g") {
          this.add = add2group;
          for (var method in Paper.prototype) if (Paper.prototype[has](method)) {
              this[method] = Paper.prototype[method];
          }
      }
```
Once Element() has returned, this duplicate code in ```elproto.group()``` is not needed, as all these have already been set:
```javascript
          el.add = add2group;
          for (var method in proto) if (proto[has](method)) {
              el[method] = proto[method];
          }
```
nor is the single duplicate line of code in make() needed:
```javascript
    function make(name, parent) {
          :   :   :   :
        var el = wrap(res);
        el.type = name;
```
This was tested first by inserting 'throw's into the code, specifically testing that the asserted behavior was true.
```
    C:\Toms\Study\Javascript\Snap.svg\github\Snap.svg\src>git diff svg.js
    diff --git a/src/svg.js b/src/svg.js
    index d347a7b..98dd52f 100644
    --- a/src/svg.js
    +++ b/src/svg.js
    @@ -2507,6 +2507,8 @@ function make(name, parent) {
         var res = $(name);
         parent.appendChild(res);
         var el = wrap(res);
    +    if (!el.type)         throw new Error("make() el.type not already set");
    +    if (el.type !== name) throw new Error("make() el.type not set correctly");
         el.type = name;
         return el;
     }
    @@ -2909,6 +2911,10 @@ function gradientRadial(defs, cx, cy, r, fx, fy) {
         \*/
         proto.group = proto.g = function (first) {
             var el = make("g", this.node);
    +        if (!el.add)                      throw new Error("elproto.group() el.a
    +        if (el.add !== add2group)         throw new Error("elproto.group() el.a
    +        if (!el.el)                       throw new Error("elproto.group() el.e
    +        if (el.el !== Paper.prototype.el) throw new Error("elproto.group() el.e
             el.add = add2group;
             for (var method in proto) if (proto[has](method)) {
                 el[method] = proto[method];
```
  This code did not throw during the tests.  Note that a one point the checks were coded wrong and did throw.

  The duplicate code was then removed and tests re-run.
```
    C:\Toms\Study\Javascript\Snap.svg\github\Snap.svg\src>diff -u svg.js.original svg.js.deduped
    --- svg.js.original     2014-03-16 20:22:37.409811000 -0500
    +++ svg.js.deduped      2014-03-16 20:54:50.497553500 -0500
    @@ -2507,7 +2507,6 @@
         var res = $(name);
         parent.appendChild(res);
         var el = wrap(res);
    -    el.type = name;
         return el;
     }
     function Paper(w, h) {
    @@ -2909,10 +2908,6 @@
         \*/
         proto.group = proto.g = function (first) {
             var el = make("g", this.node);
    -        el.add = add2group;
    -        for (var method in proto) if (proto[has](method)) {
    -            el[method] = proto[method];
    -        }
             if (arguments.length == 1 && first && !first.type) {
                 el.attr(first);
             } else if (arguments.length) {
```
While somewhat difficult to see because of the number of other errors due to bugs or browser boo-boos, neither the checking throws nor the removal of the duplicate code caused any (more) errors in the test/test.html runs.
```
FireFox  27.0.1
  no changes
      passes: 203  failures: 10  duration: 2.60s
  path2curve fix
      passes: 208  failures: 5   duration: 3.12s
  dedupe_checks
      passes: 208  failures: 5   duration: 2.76s
  deduped
      passes: 208  failures: 5   duration: 2.60s


Opera  20.0
      gets several errors due to local file:// ajax failures
  no changes
      passes: 199  failures: 14  duration: 2.03s
  path2curve fix
      passes: 202  failures: 11  duration: 2.20s
  dedupe_checks
      passes: 202  failures: 11  duration: 2.26s
  deduped
      passes: 202  failures: 11  duration: 2.18s


Chrome  33.0
      gets several errors due to local file:// ajax failures
  no changes
      passes: 199  failures: 14  duration: 1.99s
  path2curve fix
      passes: 202  failures: 11  duration: 2.19s
  dedupe_checks
      passes: 202  failures: 11  duration: 2.25s
  deduped
      passes: 202  failures: 11  duration: 2.08s


IE 10
      gets several errors due to local file:// ajax failures
  no changes
      passes: 189  failures: 24  duration: 1.87s
  path2curve fix
      passes: 195  failures: 18  duration: 2.45s
          (lovely IE)   
              Error: expected 'M 10 10 L 50 60' to equal 'M10,10,50,60'
              Error: expected '10,15 20,25 30,35' to equal '10,15,20,25,30,35'
              TypeError: Unable to get property 'nodeName' of undefined or null reference
  dedupe_checks
      passes: 195  failures: 18  duration: 1.92s
  deduped
      passes: 195  failures: 18  duration: 1.81s
```

This is obviously not a high priority change, but would help de-clutter the code.