[gherkin-perl] Add `from_paths` and `from_source` to Gherkin module
[gherkin-perl] Add `from_paths` and `from_source` to Gherkin module

Similar to the structure of the Ruby and Java implementations, support
seed a pipe line of messages (consumed through the $sink) using one
of two functions: `from_paths` and `from_source`.

cucumber/gherkin-perl,cucumber/gherkin-perl