Implement Compress Option

[EriKWDev]

I see mentions to a -c / --compress option in the comments in the code. The base64 encoded strings can become very large.

Would be nice to implement the compress option :)

Maybe using any of these:

• guzba/zippy # pure nim
• guzba/supersnappy # pure nim
• nim-lang/zip
• genotrance/nimarchive

[EriKWDev]

I thought a bit about it and I don't know how to implement this without the need for a dependency in the user's project :/

In order to compress we most likely need to depend on a separate library, but then in order to uncompress in the getAsset() proc in the assetfile, it also needs to import that library.

This means that the end project that wants to use nimassets also has to depend on the compression library.

I don't know if that's a big deal or not, but seems like the only option. I personally don't requires("nimassets") in my nimble file, but that might be what everyone else already does and that this is a non-issue.