TinyBMS breakout enclosure

Breakout enclosure for TinyBMS. For larger projects such as golf carts and stationary storage enclosure size doesn't matter as much, but what matters is ruggedness and ease of installation / access. This enclosure does the following :

* Balancing lead connectors are organized into a double stack of 16 Anderson PP15. 15 are needed for 14S configuration (current model); I will make a separate one for 16S with 18 connectors
* Pack power is via double stack of 4 Anderson PP30 or PP45. As the name suggests, PP45 is limited to 45 Amps, so doubling the connectors allows pulling full rated BMS current if necessary
* Charger and load connectors are likewise doubled on the opposite side. Since BMS can only handle 30A from charger, having an extra pin allows to wire it directly to the pack when using a smart charger and needing to bypass the BMS
* Two PP15 pins for driving external contactor
* Three keystone RJ45 or RJ11 for various things like serial communication, current and temperature