STY,MAINT: Style of coding enhanced

[surevs]

Following are the specific and detail changes which are implemented as a part of this pull request:

• possible PEP8 fixes have been done which does not affect the functionality of code
• Futures have been added to requirements to ensure things work correct as expected as python 2.7 core does not include it at requirements.txt:11
• Good to have grpc as part of requirements - requirements.txt:12
• Imported specific ThreadPoolExecutor as it is only used in start.py
• Updated the try import of collections to reflect based on python version at getgauge\python.py:6

[surevs]

Thanks a lot @sriv , Will await for your review comments.

[surevs]

• grpc has been removed from the requirements as grpcio and grpcio-tools already exists

[surevs]

@gaugebot recheck

[surevs]

@sriv please advise in case of any changes to be done .

[surevs]

@gaugebot recheck

[sriv]

@BugDiver - would you mind taking a look at this please? thanks.

[BugDiver]

@surevs Sorry for the delay. Looks like BOT had some issues validating your PR.
I checked the records manually but did not find you.
Can you please sign the CLA at https://gauge-bot.herokuapp.com/cla/
You can validate your self by browsing at https://gauge-bot.herokuapp.com/contributor?checkContributor=YOUR_USER_NAME

[surevs]

@gaugebot recheck the pull request.

[gaugebot]

This PR has been verified. The gauge team will be looking into this soon.

/cc @getgauge/core

[surevs]

thank you @BugDiver !