[Tagging] Beautified JSON presets for natural=tree

[Pander]

Hi all,

I would like to proposed some improvements to Beautified JSON presets
for natural=tree.

In short these are:
 1. rename label "Type" to "Leaf Type" for key `leaf_type` to explain
the key better and avoid confusion with key `type` which is no longer
used for trees
 2. rename label "Cycle" to "Leaf Cycle" for key `leaf_cycle` to explain
the key better
 3. add `key circumference` with label "Circumference (m)" to capture
during survey
 4. add key `diameter_crown` with label "Diameter crown (m)" to capture
during survey
 5. remove key `name` as it is rare for trees

Discussion that was the basis for this is found at
https://github.com/simonpoole/beautified-JOSM-preset/issues/18#issuecomment-317171508
Note that the proposal has already had some evolution. Subsequently,
tree_row could also benefit from a review.

Curious to your views on this.

Best,

Pander