fix broken links in new README

CONTRIBUTING.md

@@ -0,0 +1,54 @@
+# Contributing
+
+HOHQMesh.jl is an open-source project and we are very happy to accept contributions
+from the community. Please feel free to open issues or submit patches (preferably
+as merge requests) any time. For planned larger contributions, it is often
+beneficial to get in contact with one of the principal developers first (see
+[AUTHORS.md](AUTHORS.md)).
+
+HOHQMesh.jl and its contributions are licensed under the MIT license (see
+[LICENSE.md](LICENSE.md)). As a contributor, you certify that all your
+contributions are in conformance with the *Developer Certificate of Origin
+(Version 1.1)*, which is reproduced below.
+
+## Developer Certificate of Origin (Version 1.1)
+The following text was taken from
+[https://developercertificate.org](https://developercertificate.org):
+
+    Developer Certificate of Origin
+    Version 1.1
+
+    Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
+    1 Letterman Drive
+    Suite D4700
+    San Francisco, CA, 94129
+
+    Everyone is permitted to copy and distribute verbatim copies of this
+    license document, but changing it is not allowed.
+
+
+    Developer's Certificate of Origin 1.1
+
+    By making a contribution to this project, I certify that:
+
+    (a) The contribution was created in whole or in part by me and I
+        have the right to submit it under the open source license
+        indicated in the file; or
+
+    (b) The contribution is based upon previous work that, to the best
+        of my knowledge, is covered under an appropriate open source
+        license and I have the right under that license to submit that
+        work with modifications, whether created in whole or in part
+        by me, under the same open source license (unless I am
+        permitted to submit under a different license), as indicated
+        in the file; or
+
+    (c) The contribution was provided directly to me by some other
+        person who certified (a), (b) or (c) and I have not modified
+        it.
+
+    (d) I understand and agree that this project and the contribution
+        are public and that a record of the contribution (including all
+        personal information I submit with it, including my sign-off) is
+        maintained indefinitely and may be redistributed consistent with
+        this project or the open source license(s) involved.

README.md

@@ -9,7 +9,7 @@
 This package is a Julia frontend to the Fortran-based *High Order Hex-Quad Mesher*
 (a.k.a. [**HOHQMesh**](https://github.com/trixi-framework/HOHQMesh)) created and developed by
 [David A. Kopriva](https://www.math.fsu.edu/~kopriva/). It augments HOHQMesh with
-[interactive functionality](@ref InteractiveTool) that gives a user the ability to create, visualize,
+[interactive functionality](https://trixi-framework.github.io/HOHQMesh.jl/dev/interactive_overview/) that gives a user the ability to create, visualize,
 and generate high-order meshes.
 It further allows one to seamlessly integrate meshes generated by HOHQMesh into a Julia-based simulation workflow.
 For example, running a simulation on an unstructured quadrilateral mesh
@@ -83,8 +83,10 @@ files that are saved and the output of mesh statistics to the screen.
 
 ![box_two_circles](https://user-images.githubusercontent.com/25242486/174244295-40d31df3-981e-4375-bc3a-af0a43737710.png)
 
-Further explanation of the interactive functionality can be found [here](@ref InteractiveTool).
-Additional examples are available in the [Tutorials](@ref).
+Further explanation of the interactive functionality can be found [here]
+(https://trixi-framework.github.io/HOHQMesh.jl/dev/interactive_overview/).
+Additional examples are available in the [Tutorials]
+(https://trixi-framework.github.io/HOHQMesh.jl/dev/tutorials/introduction/).
 
 ## Authors
 HOHQMesh.jl is maintained by the
@@ -95,10 +97,10 @@ The *HOHQMesh* mesh generator itself is developed by David A. Kopriva.
 
 
 ## License and contributing
-HOHQMesh.jl is licensed under the MIT license (see [License](@ref)).
+HOHQMesh.jl is licensed under the MIT license (see [LICENSE.md](LICENSE.md)).
 *HOHQMesh* itself is also available under the MIT license.
 Since HOHQMesh is an open-source project, we are very happy to accept contributions
-from the community. Please refer to [Contributing](@ref) for more details.
+from the community. Please refer to [CONTRIBUTING.md](CONTRIBUTING.md) for more details.
 To get in touch with the developers,
 [join us on Slack](https://join.slack.com/t/trixi-framework/shared_invite/zt-sgkc6ppw-6OXJqZAD5SPjBYqLd8MU~g)
 or [create an issue](https://github.com/trixi-framework/HOHQMesh.jl/issues/new).