Make cleaner separation between parser and main.

[jonathf]

Currently the main interface creates CLArgs to parser arguments, which (depending on input) get passed down into the vroom machinery.
For the most part this is done cleanly in such a way that you don't need CLArgs to use any machinery, with input parser being the only exception.

I propose we make the interface cleaner by keeping CLArgs contain to the main file and just passing it's attribute along explicitly.

Issue

#665

Tasks

• Update CHANGELOG.md
• review

[jcoupey]

Simple change but a good readability improvement. I guess this is the benefit of having people look at the code from a "downstream" perspective! ;-)

[jonathf]

I've pushed updated changes now.

To avoid the issue with requiring known amount_size, I set some asserts in place to assure that amount_size is always defined first.

If you think this is too invasive, I will be happy to roll back to the first iteration (with suggestions) and continuing the conversation for a new PR in the #665.

[jcoupey]

This is clean. We're loosing constness of Input::_amount_size but I think it's fine since it's private and users have to do things right anyway via set_amount_size.

[jonathf]

I've applied alll suggestions and rebased the branch to the tip of master.

[jcoupey]

The PR shows up as closed since I messed a bit with the branch but it's merged all right. Looks like GitHub is confused as I squashed the last bugfixes commits into a single one and pushed the merge commit to master before force-pushing this branch.