fix: allow method override in request body

[shaunwarman]

Allow request body to honor _method property to override http method to DELETE and PUT where necessary.

relates to: ladjs/lad#395

[codecov]

Codecov Report

Merging #25 into master will decrease coverage by 0.13%.
The diff coverage is 83.33%.

@@ Coverage Diff @@ ## master #25 +/- ## ========================================== - Coverage 84.13% 84.00% -0.14%  ========================================== Files 1 1 Lines 145 150 +5 ========================================== + Hits 122 126 +4  - Misses 23 24 +1 

Impacted Files	Coverage Δ
index.js	84.00% <83.33%> (-0.14%)	⬇️

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[shaunwarman]

updated @niftylettuce - can add method override similar to the below upstream (lad / FE / etc):

(req) => { const { _method } = req.body; if ( typeof _method !== 'string' && !['PUT', 'DELETE'].includes(_method) ) { throw new Error(`method override of ${_method} is not valid`); } return _method; })