Prepending time formats when using RegisterTimeFormats

[paganotoni]

This PR changes the way we add time formats when using RegisterTimeFormats, instead of appending the PR's the developer is passing we should prepend these to the list of formats, that is to give more importance to the time formats passed by developers than defaults.

As an example if we call RegisterTimeFormats("2006-02-01") and try to parse a date like 2017-01-10 buffalo our be using 2006-01-02 which is one of the defaults, instead of using the time format we just registered.

This PR prepends developer-added formats so these get evaluated first.

[codecov]

Codecov Report

Merging #1170 into development will increase coverage by 0.05%.
The diff coverage is 100%.

@@               Coverage Diff               @@
##           development    #1170      +/-   ##
===============================================
+ Coverage         50.6%   50.65%   +0.05%     
===============================================
  Files               74       74              
  Lines             3794     3794              
===============================================
+ Hits              1920     1922       +2     
+ Misses            1757     1755       -2     
  Partials           117      117

Impacted Files	Coverage Δ
binding/binding.go	45.78% <100%> (+2.4%)	⬆️

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