Two more regression samples & fix bug on thumbnail upside down

[julien2512]

2 more reg samples :

• Maximum
• RegMax

Thumbnail were also upside down ! The problem is thumbnails and network are not generated the same way (network comes from svg data). The easiest was to fix the renderThumbnail function.

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[julien2512]

I signed it!

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[julien2512]

@googlebot You're welcome.