feat : adding alarms API

[kabir-afk]

Changes

• chore:added alarms permission - added alarms permission in manifest.json
• feat : added alarm functionality - added alarm functionality inside service_worker. Despite minimum period being 0.5 minutes for an alarm , if we set it it as fraction , we can trigger it in 10 seconds as shown in commit.

Whats actually happening is , whenver user selects the extension icon, along with getBackground command createAlarm function is triggered , which creates the alarm. Now our alarm isn't supposed to do anything , we don't have to do any periodic tasks like pinging the user to drink water after 1 min ,etc. We just have to wait for the state of the extension ot be ready and once it is ready , it will send a message to the popup which upon receving the message will initialize the UI, as mentioned in refactor: Initialize UI with respect to alarms API.

• revert : keeping the old approach for Firefox - While alarms are the best approach when working with service_workers , the old approach of using setTimeout still works in persistent backgroundPage which we use for Firefox. So keeping it now for temporary testing purposes.

[Ishan-Saini]

LGTM

[hugolpz]

After the merge by Ishan, @kabir-afk added an additional commit.

@Ishan-Saini, How to proceed with it ? Any experience and best practices with such cases ?

[kabir-afk]

Didn't notice it earlier , pardon me for those changes. I had some conflicts with my master branch due to which it was populated with some unwanted past commits..hence to fix it I fetched and resetted my remote and local branch leading to this commit

[hugolpz]

@kabir-afk , can you ensure the master branch also get this https://github.com/kabir-afk/SignIt/commit/e97ed9365045314bd2979bd9ec8f397d259ee637 code ?