Unmarshaling is incorrect, particularly around numbers.

[beiriannydd]

Minimal example

https://play.golang.org/p/jZK6kGxo_vB

for '--- 1' og vs output: (int)1!=(float64)1
for '--- 031' og vs output: (int)25!=(float64)25
for '--- 031' ogoutstring vs outstring: 031!=25
for '--- 031' ogoutnum vs outnum: 031!=25
for '--- {"hi":031}' og vs output: (map[interface {}]interface {})map[hi:25]!=(map[string]interface {})map[hi:25]
err: error unmarshaling JSON: json: cannot unmarshal object into Go value of type string
err: error unmarshaling JSON: json: cannot unmarshal object into Go value of type json.Number

I'm ok with many of these. What I really want though is for json.Number to be decoded without 0 truncation and octal conversion as the OG yaml library does.