Distribution generates CommonJS and ES6, removal of bs58 dependency (not used in code)

[ochaloup]

Changing the distribution to be run with both commonjs and es6 module types.
Webpack minified version is left intact.

[ochaloup]

Just wondered if makes sense to have build different module versions. Similar to how it's referred at e.g., here https://stackoverflow.com/a/58724355/187035

[ochaloup]

I would like to ask for re-review @AlexStefan @MjCage

What I did. I checked the jupiter, mango and anchor how they build their packages. From that it can be seen there is normal to build both types of packages - esm and commonjs (https://github.com/blockworks-foundation/mango-v4/blob/dev/package.json#L19). When I tried without commonjs on my testing project https://github.com/ochaloup/marinade-ts-sdk-example - which is a nodejs project - I've got issues to get it running (while I'm not still an expert to say that I could not be missing some conf that it could work without having that type of module, anyway).

The build process now generates the both types of modules and both types of modules in minified version with webpack.

I think this part of the update is fine to be reviewed and in case merged.

(Where I still fight at is the tree-shaking process for a dependent library. I'm not able to make tree shaking to work when using marinade-ts-sdk in my test project.)

[ochaloup]

I'm converting this to Draft. I need a little bit more discussion on this topic before finalizing the PR.

[ochaloup]

I changed the PR and it's ready for review.

We discussed that the work consists of two parts

1. module distribution (covered by this change, ready for review). Inspiration came from mango-v4 repository and other projects.
2. refactoring of the code to be more tree shakable and consists of functions rather than all covered in classes. this part need more investigation and discussions.

[ochaloup]

I changed this PR to draft as the work was put on hold and some more points are needed to be done on top of this drafted PR.