4.8.0

1. Many improvements in the I/O part
   • support most of STL containers
   • support TMap and TClonesArray containers
   • all kind of multidimensional arrays
   • correct treatment of foreign classes
   • supports different versions of class in the same file
   • support members like ClassName* fField; //[fCnt]
   • support const char*
   • support fixed-size array of TString, TObject and TNamed
2. Many new draw options for different classes are supported:
   • TGraph - 'z', 'x', '||', '[]', '>', '|>', '5', 'X+', 'Y+'
   • TH1 - '*', 'L', 'LF2', 'B', 'B1', 'TEXT', 'E0', 'E3', 'E4', 'EX0', 'X+', 'Y+'
   • TH2 - 'E', 'col1', 'box', 'box1', 'surf3', 'surf7', 'base0'
   • TH2 - 'same' with 'box', 'col', 'cont', 'lego', 'surf'
   • TH3 - 'scat', use by default
   • TF1/TF2 - 'nosave' to ignore saved buffer
   • TCanvas - logx/y/z, gridx/y, tickx/y
   • THStack - 'lego' and other 3D draw options
3. Implement drawing of TProfile2D, TF2, TGraph2D, TGraph2DErrors and TMarker
4. Fix - correctly place TGAxis relative to frame (when exists)
5. When superimpose items, one can specify individual options
   ...&item=histo1+histo2&opt=hist+e1
   ...&item=[histo1,histo2]&opt=[hist,e1]
6. Support loading of TStyle object, providing in URL
   ...&style=item_name or ...&style=json_file_name
   All values are copied directly to JSROOT.gStyle object.
7. Add callback argument into JSROOT.draw() function.
   Function will be called after drawing of object is completed.
   Painter for drawn object will be provided as first argument (or null in case of error).
8. Improve cleanup of JSROOT objects