fix VhdlExtractor.is_array + use setup.cfg + clean

[kammoh]

• start using setup.cfg
• fix VhdlExtractor.is_array (used in symbulator) which was completely broken
• avoid adding log handler (unless no handlers already exist), to avoid messing up caller's logger.
• verilog_parser: more rebust endmodule identification
• fix identification of file extension (e.g. my.module.v)
• consider '.sv' file extension as (System)Verilog