toml.Unmarshaler supports leaf nodes

[pelletier]

Fixes #437

[codecov]

Codecov Report

Merging #444 into master will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #444      +/-   ##
==========================================
+ Coverage   93.90%   93.91%   +0.01%     
==========================================
  Files          10       10              
  Lines        2443     2448       +5     
==========================================
+ Hits         2294     2299       +5     
  Misses        108      108              
  Partials       41       41              

Impacted Files	Coverage Δ
marshal.go	96.32% <100.00%> (+0.02%)	⬆️

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[x1unix]

@pelletier I recommend you to take a look at github.com/stretchr/testify package.

It contains a set of handy tools for unit tests - require and assert

// assert.NoError is also ok, but require will stop test if condition is failed
require.NoError(t, err)
require.EqualError(t, err, "some error message")
require.Equal(t, expected, cfg.HTTP.PingTimeout)

[pelletier]

Thanks!