add arj compression

[IgorZolin]

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Add arj archives decompression.

[garydgregory]

@IgorZolin
Modified how? Can we reduce the copy pasta and have a shared implementation?

[IgorZolin]

Sorry, it was not really modified, just don't want to change someones code. I could make lha.CircularBuffer public and reuse it (there would be some risk that changes in lha could broke arj).

[garydgregory]

That's what unit tests are for ;)

[garydgregory]

You didn't follow the template instructions, so the build is broken...

[IgorZolin]

You didn't follow the template instructions, so the build is broken...

sorry, i've fix lint promlems, can we run build?

[fkjellberg]

Hi @IgorZolin

Thanks for improving ARJ decompression support. Please take a look at my PR 812 which replaces the BinaryTree implementation with the new HuffmanDecoder for LHA. The same refactor should work here as well. It will improve code reuse and significantly reduce memory usage.

[IgorZolin]

ok, i can pause my pr and update it after yours pr would be merged?