Took Tess' RXTE light curve notebook idea from SciServer and wrote new version

.circleci/config.yml

@@ -139,7 +139,7 @@ jobs:
       # Now we're going to start building the documentation
       - run:
           name: Build HTML rendering of notebooks
-          no_output_timeout: 30m
+          no_output_timeout: 75m
           command: |
             # The first command sets the HEASARC_NOTEBOOKS_TO_BUILD environment variable, which tells the build
             #  process which notebooks to build. It allows granular control over which notebooks are built

.github/pull_request_template.md

@@ -32,6 +32,7 @@ The author of the pull request should make an effort to go through these check p
 - [ ] Have you populated the notebook front-matter (the metadata at the top of the notebook)?
 - [ ] Is the kernel specified in the front-matter (e.g., heasoft, sas, ciao) correct for the notebook?
 - [ ] Have you added an entry for your notebook in the *_index.md file for the containing directory?
+- [ ] Is all plotting matplotlib (or alternative) plotting code in isolated cells, and do they have the metadata required to collapse the code when the notebook/website is viewed?
 
 ### Tech review checklist
 - Documentation:

notebook_template.md

@@ -94,7 +94,11 @@ code cell - it will be minimized unless the user decides to expand it. **Please
 explanations of your functions or remove it if there are no functions.**
 
 ```{code-cell} python
-:tags: [hide-input]
+---
+tags: [hide-input]
+jupyter:
+  source_hidden: true
+---
 
 # This cell will be automatically collapsed when the notebook is rendered, which helps
 #  to hide large and distracting functions while keeping the notebook self-contained
@@ -104,14 +108,22 @@ explanations of your functions or remove it if there are no functions.**
 ### Constants
 
 ```{code-cell} python
-:tags: [hide-input]
+---
+tags: [hide-input]
+jupyter:
+  source_hidden: true
+---
 
 ```
 
 ### Configuration
 
 ```{code-cell} python
-:tags: [hide-input]
+---
+tags: [hide-input]
+jupyter:
+  source_hidden: true
+---
 
 ```
 
@@ -139,16 +151,34 @@ This helps people understand both the notebook and the data so that they're more
 +++
 
 :::{tip}
-Please include narrative along with *all* your code cells to help the reader figure out what you are doing and why you chose that path.
+Please include a narrative for *all* your code cells to help the reader figure out what you are doing and why you chose that path.
 
 Using [MyST admonitions](https://mystmd.org/guide/admonitions) such as this `tip` are encouraged
 :::
 
 ```{code-cell} python
+---
+tags: [hide-input]
+jupyter:
+  source_hidden: true
+---
+
 hist, bin_edges = np.histogram(data, bins=10)
 hist
 ```
 
+:::{important}
+The HEASARC-tutorials style guide requires that cells using matplotlib (or similar) to produce figures
+should be isolated (i.e., only contain plotting code), and must include the following metadata to hide the
+code from view (see the source of this cell for the unrendered text:
+
+---
+tags: [hide-input]
+jupyter:
+  source_hidden: true
+---
+:::
+
 For any Figures, please add a few sentences about what the users should be noticing.
 
 +++