Add possibility to choose output key (id or name)

[duergner]

Fixes #102

[codecov-io]

Codecov Report

Merging #103 into master will decrease coverage by 0.01%.
The diff coverage is 86.66%.

@@             Coverage Diff              @@
##             master     #103      +/-   ##
============================================
- Coverage     78.91%   78.89%   -0.02%     
- Complexity      306      308       +2     
============================================
  Files             5        5              
  Lines           863      867       +4     
============================================
+ Hits            681      684       +3     
- Misses          182      183       +1

Impacted Files	Coverage Δ	Complexity Δ
src/EDI/Interpreter.php	90.32% <86.66%> (-0.26%)	85 <2> (+2)

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[sabas]

@duergner instead of the constructor, what about making it a flag with a function, like I made in fogglePatching
https://github.com/php-edifact/edifact/blob/master/src/EDI/Interpreter.php#L121

[duergner]

Changed it as suggested.

Shall I add the fix for the failing tests as well to this PR (even though it would be unrelated)

[sabas]

Shall I add the fix for the failing tests as well to this PR (even though it would be unrelated)

Yes thank you :)

[duergner]

Build should come back to green and I added a test for the new functionality