Adding files

[Nathalie-Leenders]

We're so eager to add your sample to this repository as soon as possible, but we need all samples follow the same structure.
To make sure we process it as soon as possible, make sure to follow these instructions.

Q	A
Bug fix?	no
New feature?	yes
New sample?	yes
Related issues?

Solution Details

Q	A
Solution requires premium license	yes
Solution uses experimental features (see licensing guidelines)	no
Which connectors are used?	DataVerse
Solution uses on-premises connectors?	no
Solution uses custom connectors?	no
Layout	Tablet

What's in this Pull Request?

This is a new holiday sample, created together with Keith Atherton to display how a gallery works, while having fun and learning along the way in a holiday theme.

[Katerina-Chernevskaya]

Hi @Nathalie-Leenders,

Thank you for your contribution!
I tried to pack the source code into a solution and got the following error:

Could you please check that all source code files are in place and upload them? Please follow the steps described in the guide to prepare the source code files.

Also please rename your folder with lower-case letters, use dashes instead of spaces. Like this: christmas-advent-calendar

Thank you in advance!

Regards,
Katerina Ch.