Added Contribute notebook to table of contents

Author: seanlaw

…/Tutorial_First_Time_Contributions.ipynb docs/Contribute.ipynbdocs/Tutorial_First_Time_Contributions.ipynb renamed to docs/Contribute.ipynb docs/Tutorial_First_Time_Contributions.ipynb renamed to docs/Contribute.ipynb

@@ -10,6 +10,7 @@ STUMPY documentation
    install
    api
    tutorials
+   Contribute.ipynb
    help
    Code Repository <https://github.com/TDAmeritrade/stumpy>