combostew 0.1.2

Combostew is an intermediate layer between the image crate and the 'sic' and 'stew' image tool front-ends.
Documentation
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A description about what is included in this update, a thank you or something
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### Changes from `current version` to `new version`:

- ... (issue: #X, PR: #Y)
- ... (issue: #X, PR: #Y)
- ... (issue: #X, PR: #Y)

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### Problems encountered & their resolutions


Blocking:
- [ ] ... (issue: #X, PR: #Y)
- [ ] ... (issue: #X, PR: #Y)
- [ ] ... (issue: #X, PR: #Y)

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### Release checklist


**Create Release PR**

- [ ] Included this checklist. Already a step complete! :wink:

**Verify**

- [ ] Verify formatting with `cargo +nightly fmt`.
- [ ] Does `cargo test` succeed?
- [ ] Verify image output of images produced with `cargo test --features output-test-images`.
- [ ] Do all CI runs complete successfully?


**Update version number**

- [ ] Define update version number [as described here]https://doc.rust-lang.org/cargo/reference/publishing.html#publishing-a-new-version-of-an-existing-crate.
- [ ] Update the version number in `Cargo.toml`.
- The Clap App version numbers will be equal to the version number in `Cargo.toml`.


**Update the dependency licenses to be included in the binary as per their licenses**

- [ ] Run `cargo run --example update_dep_licenses` to update the licenses of dependencies, which will be included in a binary build.

**Verify again**

Same as above.

- [ ] Completed!

**Merge Release PR**

If no blocking issues are detected and this checklist is complete,
we can move on to the next step.

**Publish & Upload**

- [ ] Run `cargo package` and check the resulting `.crate`
- [ ] Run `cargo publish` and verify the result

**Release, Tag & Binaries**

- [ ] Create a release with a version tag on [the github release page]https://github.com/foresterre/stew/releases
    - tags are equal to crate version number e.g. `0.5.1`
    - release title is `stew-<version>` e.g. `stew-0.5.1`


- [ ] Add Windows and Linux (Ubuntu compiled) binaries to the release
    - compile with `cargo build --release`

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[Release steps](https://github.com/foresterre/stew/blob/master/RELEASE_STEPS.md)

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PR: #<PR NUMBER>