Herdable upgrade

There are upgrades that increase carry capacity, and gather rate of:
Fish, Berries, and Huntables. The huntable's upgrade even increases
the damages against huntables by 50%.

There are no upgrades for increasing the effectiveness of using herdables.
My suggestion is this: The developers should create an upgrade in the
storehouse for age 1 that opens up a meta strategy for herdables.

There is the picker's glove for berries, hunting dogs for hunts,
and now finally, rancher's feed:

Rancher's Feed

Increases total food of herdable animals by 25%

1. From 150 to 187, adds 37 to total food
2. that's 74 more food per pair found

* If possible: Scout Unit lures nearby non-player controlled
herdables within its Line-Of-Sight. (herdables follow the scout)

Allows easier pasturing

1. hotkey for sending herdables to town center once captured
   (instead of garrison hotkey, which herdables don't have)