MyHose T-adapter

Paul tibble's Hose connector works all right but I needed a T-connector to dispatch my drip system. So I designed it starting from his design, with some hard-coded stuff.

Designed for 16mm irrigation hose.

To be printed on the long side.

Als a few minor enhancements:
* the first barb has a 5mm offset from the mouth
* the innermost bard is a bit higher
* top and side barbs are not 90° on the inner side, so that it prints Ok without any support.

Needs a bit of finishing