fix composers to accept 0 address

[aldas]

fixes #27

[codecov]

Codecov Report

Merging #28 into master will not change coverage.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master      #28   +/-   ##
=========================================
  Coverage     87.22%   87.22%           
  Complexity      611      611           
=========================================
  Files            51       51           
  Lines          1472     1472           
=========================================
  Hits           1284     1284           
  Misses          188      188

Impacted Files	Coverage Δ	Complexity Δ
src/Composer/Write/WriteRegistersBuilder.php	100% <100%> (ø)	38 <0> (ø)	⬇️
src/Composer/Read/ReadRegistersBuilder.php	99.08% <100%> (ø)	48 <0> (ø)	⬇️

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