segmentation violation when input directory doesn't exist

[reuvenharrison]

To replicate, in go-localize root, run:

go-localize -input localizations_src -output localizations

Result: panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x18 pc=0x116cefe]

goroutine 1 [running]: main.getLocalizationFiles.func1({0x7ff7bfeff3f3, 0x11}, {0x0?, 0x0?}, {0xc000074200?, 0x0?}) /Users/Reuven/view/go/src/github.com/m1/go-localize/main.go:88 +0x7e path/filepath.Walk({0x7ff7bfeff3f3, 0x11}, 0xc00012be90) /usr/local/go/src/path/filepath/path.go:570 +0x4a main.getLocalizationFiles({0x7ff7bfeff3f3?, 0x10fd1ea?}) /Users/Reuven/view/go/src/github.com/m1/go-localize/main.go:86 +0x48 main.run(0xc000108000?, 0xc0000140b0?) /Users/Reuven/view/go/src/github.com/m1/go-localize/main.go:57 +0x7a main.main() /Users/Reuven/view/go/src/github.com/m1/go-localize/main.go:46 +0x6e