Add recipe for mrtrix3

[martin-g]

Describe your pull request here

---

Please read the guidelines for Bioconda recipes before opening a pull request (PR).

General instructions

• If this PR adds or updates a recipe, use "Add" or "Update" appropriately as the first word in its title.
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Instructions for avoiding API, ABI, and CLI breakage issues

Conda is able to record and lock (a.k.a. pin) dependency versions used at build time of other recipes.
This way, one can avoid that expectations of a downstream recipe with regards to API, ABI, or CLI are violated by later changes in the recipe.
If not already present in the meta.yaml, make sure to specify run_exports (see here for the rationale and comprehensive explanation).
Add a run_exports section like this:

build:
  run_exports:
    - ...

with ... being one of:

Case	run_exports statement
semantic versioning	{{ pin_subpackage("myrecipe", max_pin="x") }}
semantic versioning (0.x.x)	{{ pin_subpackage("myrecipe", max_pin="x.x") }}
known breakage in minor versions	{{ pin_subpackage("myrecipe", max_pin="x.x") }} (in such a case, please add a note that shortly mentions your evidence for that)
known breakage in patch versions	{{ pin_subpackage("myrecipe", max_pin="x.x.x") }} (in such a case, please add a note that shortly mentions your evidence for that)
calendar versioning	{{ pin_subpackage("myrecipe", max_pin=None) }}

while replacing "myrecipe" with either name if a name|lower variable is defined in your recipe or with the lowercase name of the package in quotes.

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Please use the following BiocondaBot commands:

Everyone has access to the following BiocondaBot commands, which can be given in a comment:

@BiocondaBot please update	Merge the master branch into a PR.
@BiocondaBot please add label	Add the please review & merge label.
@BiocondaBot please fetch artifacts	Post links to CI-built packages/containers. You can use this to test packages locally.

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[martin-g]

@BiocondaBot please fetch artifacts

[BiocondaBot]

Package(s) built are ready for inspection:

Arch	Package	Zip File / Repodata	CI	Instructions
linux-64	mrtrix3-3.0.4-ha1f1e50_0.tar.bz2	linux-64.zip	GitHub Actions	show You may also use conda to install after downloading and extracting the zip file. conda install -c ./packages <package name>
linux-aarch64	mrtrix3-3.0.4-hc97f590_0.tar.bz2	repodata.json	CircleCI	show You may also use conda to install:conda install -c https://output.circle-artifacts.com/output/job/219ff67a-48e9-4d75-b1f4-0cbc1599a360/artifacts/0/tmp/artifacts/packages <package name>

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Docker image(s) built:

Package	Tag	CI	Install with docker
mrtrix3	3.0.4--ha1f1e50_0	GitHub Actions	show Images are in the linux-64 zip file above.gzip -dc images/mrtrix3---3.0.4--ha1f1e50_0.tar.gz | docker load

[martin-g]

@BiocondaBot please fetch artifacts

[BiocondaBot]

Package(s) built are ready for inspection:

Arch	Package	Zip File / Repodata	CI	Instructions
linux-64	mrtrix3-3.0.4-ha1f1e50_0.tar.bz2	linux-64.zip	GitHub Actions	show You may also use conda to install after downloading and extracting the zip file. conda install -c ./packages <package name>
linux-aarch64	mrtrix3-3.0.4-hc97f590_0.tar.bz2	repodata.json	CircleCI	show You may also use conda to install:conda install -c https://output.circle-artifacts.com/output/job/9846e6ca-ba56-406a-bdb8-2fd896dbb670/artifacts/0/tmp/artifacts/packages <package name>

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Docker image(s) built:

Package	Tag	CI	Install with docker
mrtrix3	3.0.4--ha1f1e50_0	GitHub Actions	show Images are in the linux-64 zip file above.gzip -dc images/mrtrix3---3.0.4--ha1f1e50_0.tar.gz | docker load

[martin-g]

@BiocondaBot please add label