- Fix Catalog JSON table crash when no Jpath

- Added JSON OBJECT specification for pretty != 2.
- Fix NULL values not recognized for nullable JSON columns
- Issue an error message when a JSON table is created without specifying LRECL if PRETTY != 2.
- Make JSONColumns use a TDBJSON class.
- Make JSON table using MAPFAM
modified:
  filamap.h
  filamtxt.h
  ha_connect.cc
  json.result
  tabjson.cpp
  tabjson.h
  table.cpp

- Implementing Discovery for the XML table type.
modified:
  domdoc.cpp
  domdoc.h
  ha_connect.cc
  libdoc.cpp
  plgxml.cpp
  plgxml.h
  reldef.cpp
  reldef.h
  tabxml.cpp
  tabxml.h

- Providing an error message when creating an ODBC table via discovery returns
  columns of more than one table.
modified:
  ha_connect.cc

- TableOptionStruct declaration moved from ha_connect.h to mycat.h
  To make it easier to use by other classes.
modified:
  ha_connect.cc
  ha_connect.h
  mycat.cc
  mycat.h
  reldef.cpp
  tabmysql.cpp
  taboccur.cpp
  tabpivot.cpp
  tabtbl.cpp
  tabutil.cpp
  tabxcl.cpp

storage/connect/tabmysql.cpp

@@ -56,7 +56,6 @@
 #include "xtable.h"
 #include "tabcol.h"
 #include "colblk.h"
-#include "mycat.h"
 #include "reldef.h"
 #include "tabmysql.h"
 #include "valblk.h"