Cleaned and updated the notebooks

[YoshikiOhtani]

This pull request cleans and updates the notebooks used for checking the data produced by the combined analysis pipeline. Let me briefly clarify what's changed:

check_coincidence_performance.ipynb

• renamed to "check_event_coincidence.ipynb"
• since the data format of coincident event files was changed, the content was outdated. So I updated it so as to work for recent data files.

check_signal_from_dl2.ipynb

• just cleaned the contents and made them more user friendly style

check_irfs_from_dl2.ipynb

• not it computes energy-dependent theta2 cuts satisfying a gamma efficiency, and they are applied to the data before estimating the effective area, energy resolutions and biases

check_sed_from_dl3.ipynb

• now it follows what's done in the lstchain's notebook (notebooks/post_DL3_analysis.ipynb).
• a target position is extracted from input DL3 data files so no need to set it in the notebook
• uses the stacked analysis method when fitting a model to input dataset

Since they are used for just checking the dataset and not used for data processes, I think it does not harm anything and so would like to merge it to the master branch. Please let me know or open an issue or a pull request if you have any questions, suggestions and comments.

[review-notebook-app]

Check out this pull request on 

See visual diffs & provide feedback on Jupyter Notebooks.

---

Powered by ReviewNB