Added an alternate apt-get command for pyzbar

[sherlockhoe90]

Loved your project!

I tried to run the project on three different Ubuntu systems.
But despite trying to download 'pyzbar' from the requirements using the pip command, and it being downloaded successfully...
It always gave out the error: "[ImportError: Unable to find zbar shared library on Flask]"

In this PR I've added an alternate apt-get command so that the non tech-savvy users don't feel inconvenienced by the error.

[rahul2002m]

Loved your project!

I tried to run the project on three different Ubuntu systems. But despite trying to download 'pyzbar' from the requirements using the pip command, and it being downloaded successfully... It always gave out the error: "[ImportError: Unable to find zbar shared library on Flask]"

In this PR I've added an alternate apt-get command so that the non tech-savvy users don't feel inconvenienced by the error.

I noticed the pip install command was removed from the file. Since not all systems support apt-get, could you please update your pull request to include this change? Once that's done, I'll be happy to merge it. Thank you!

[sherlockhoe90]

@rahul2002m Made the required changes and added the pip command back again. Sorry for the delay, I'd missed your comment earlier.

[sherlockhoe90]

@rahul2002m a friendly reminder