exa.Editor meta kwarg behaves as though it is class level

[tjduigna]

Experiencing the following bug with a minimal working example:

t = exa.Editor('')
t.meta['name'] = 'main'
t.meta

returns

{'name': 'main'}

as expected. Then creating a new instance

b = exa.Editor('')
b.meta['name'] = 'face'
b.meta

returns

{'name': 'face'}

also as expected. But then:

t.meta

returns

{'name': 'face'}

as though meta is a class-level attribute of the Editor, not an instance attribute.