support 'cwd' as an argument of 'from' option

[taichi-ishitani]

#33

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (5f8e291) 99.86% compared to head (37763f2) 99.87%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master      #34   +/-   ##
=======================================
  Coverage   99.86%   99.87%           
=======================================
  Files          15       15           
  Lines        1538     1616   +78     
=======================================
+ Hits         1536     1614   +78     
  Misses          2        2           

Files Changed	Coverage Δ
lib/flgen/file_list.rb	100.00% <100.00%> (ø)
spec/flgen/file_list_spec.rb	100.00% <100.00%> (ø)

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.