Fix Common Errors on Demo/Configs

[Dogacel]

I have seen lots of inconsistencies among demo and config files. I have tried to resolve some. I think the performance of the models are also not so good. This might be related to low recall values. But still I see room for improvement. Also please consider updating MODEL_ZOO.md because it looks like there are lots of incompatible / misplaced models there.

Fixes #124, fixes #117, fixes #99, fixes #87, fixes #86, fixes #50

[Dogacel]

@lindahua @liuziwei7 @lijiancheng0614 I am planning to close this PR if it is not worth it. It's been a while since I worked with this, would be glad if you can take a quick look.

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