Landscape improvement

[Hexcles]

Fixed/suppressed several errors.

Please merge #65 first.

[landscape-bot]

Repository health increased by 3% when pulling 2d86a0d on Hexcles:landscape-improve into 882ca63 on taizilongxu:master.

• 2 new problems were found (including 2 errors and 0 code smells).
• 11 problems were fixed (including 1 error and 10 code smells).

[landscape-bot]

Repository health increased by 4% when pulling 8728dbb on Hexcles:landscape-improve into 882ca63 on taizilongxu:master.

• No new problems were introduced.
• 11 problems were fixed (including 1 error and 10 code smells).

[landscape-bot]

Repository health increased by 4% when pulling d91f85e on Hexcles:landscape-improve into 882ca63 on taizilongxu:master.

• No new problems were introduced.
• 11 problems were fixed (including 1 error and 10 code smells).

[taizilongxu]

cool!!