bug for overwrite-tables option

[recall704]

i have two table in one db, name like xxx and xxx.bak, when i use --overwrite-tables for myloader, DROP TABLE IF EXISTS for xxx.bak will be ignore

[recall704]

[recall704]

if table name is xxx.bak, the value of split_file[1] will be xxx but not xxx.bak

[davidducos]

The solution for this kind of issue, is to check the amount of elements in the split_file variable and concat again to get the real table name OR you could avoid using '.' (dot) in your table names. Pull request fixing it are welcome.

[davidducos]

We are going to start a project which is not going to allow problematic filenames for myloader. It will be a check function on mydumper, other issue releated to this: #212