Calculating the absolute fee from a fee rate can currently be achieved
by creating a `Weight` object and using
`FeeRate::checked_mul_by_weight`. This is kind of hard to discover, we
can add two public convenience functions that make discovery of the
functionality easier.
Add two functions for calculating the absolute fee by multiplying by
weight units (`Weight`) and virtual bytes (by first converting to weight
units).
We currently use the functions `min_value` and `max_value` because the
consts were not available in Rust 1.41.1, however we recently bumped the
MSRV so we can use the consts now.
Currently we have a mishmash of attribution lines accompanying the SPDX
identifier. These lines are basically meaningless because:
- The date is often wrong
- The original author attributed is not the only contributor to a file
- The term "rust bitcoin developers" is basically just noise
Just remove all the attribution lines and be done with it. While we are
at it add an SPDX line to the few files missing it, whether this license
nonsense is even needed is left as an argument for another day.
Currently we implement string parsing for height/time from the
`absolute` module but not the `relative` module.
Improve the macros used to implement string parsing and use the new
versions to implement string parsing for the height and time types in
`relative`.
Use of general-purpose integers is often error-prone and annoying. We're
working towards improving it by introducing newtypes.
This adds newtypes for weight and fee rate to make fee computation
easier and more readable. Note however that this dosn't change the type
for individual parts of the transaction since computing the total weight
is not as simple as summing them up and we want to avoid such confusion.
Part of #630