Tutorial fixes for current openCARP

What does this MR do?

Fixed most of the tutorials so they are able to run with the current openCARP version. Mostly exchanging model and model variable names, e.g. TT2->tenTusscherPanfilov or Ca_i->Cai. Some of the commits have additional comments to exchange diagrams but I can't do that.

Related issues

#38 (closed)

.gitlab/merge_request_templates/Merge_Request_Template.md

@@ -8,13 +8,13 @@
 
 ### Author's checklist
 
-- [ ] Follow the [Contribution Guidelines](https://opencarp.org/dev/community/contribute).
+- [ ] Follow the [Contribution Guidelines](https://opencarp.org/community/contribute).
 - [ ] Apply the appropriate labels.
 - [ ] Does this commit add new dependencies (e.g. Python modules)? If yes, please evaluate carefully if the additional dependency is a more sustainable option than including the functionality in own code. If the former, describe the dependency clearly, add them to the Software Management Plan and the installation instructions (*.md files, CMake files, Docker files etc.).
 
 ### Reviewer's checklist
 
-All reviewers can help ensure accuracy, clarity, completeness, and adherence to the [Contribution Guidelines](https://opencarp.org/dev/community/contribute).
+All reviewers can help ensure accuracy, clarity, completeness, and adherence to the [Contribution Guidelines](https://opencarp.org/community/contribute).
 
 **Reviewer**