Replicator Mini - Build plate support tougher version

This is not my idea idea, I just adapted it to my liking and...
Well, share with people like he was kind enough to do so before me.

Remix of: http://www.thingiverse.com/thing:615358
By: muzz64

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The original design was good, a bit wide in the locking part but good. Until I found that on my machine the support would eventually slip from side to side and doesn't support the very end of the build plate.

If I was going to put a support underneath, I wanted it as tough as I can while keeping it cost efficient, easy to print and lightweight.

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It's wider, longer and thicker (you already hear that from someone else didn't you...).

Being almost the same size in lengh (minus 0.75mm) as the under part of the stock build plate, it will limit the movement from side to side (X axis).

As the width is also close to the build plate (minus 2 to 3 mm) it will support the whole plate (Z axis).

To prevent the support from moving around, there's 3 pin that