@easysql     add splitter function which split the table to subtable. user can override it to user's split logical.     add _hashtablets to set he tablet hash value.     remove the try ... except in _conv     removed the setsplitter method     fix bug of return value in append method, when duplicate, it will return None now.
@easysql
    add splitter function which split the table to subtable. user can override it to user's split logical.
    add _hashtablets to set he tablet hash value.
    remove the try ... except in _conv
    removed the setsplitter method
    fix bug of return value in append method, when duplicate, it will return None now.
dainan13/py-aluminium,hackshel/py-aluminium