added download csv feature for contact and elecktricity

[arpit456jain]

Related Issuse

download csv feature for contact and electricity table

Closes: #227

Describe the changes you've made

A clear and concise description of what you have done to successfully close your assigned issue. Any new files? or anything you feel to let us know!

Checklist:

• [x] My code follows the style guidelines of this project.
• [x] I have performed a self-review of my own code.
• [x] I have commented my code, particularly in hard-to-understand areas.
• [ ] I have made corresponding changes to the documentation.
• [x] My changes generate no new warnings.

Screenshots

Original	Updated
original screenshot	updated screenshot

[arpit456jain]

@khannakshat7 please review it

[arpit456jain]

@khannakshat7 i tried for user also but its not working as i want it was creating a new table of user under electricity app that's why i did't commit changes for it

I implemented this feature for contact and electricity table

[arpit456jain]

@khannakshat7 please merge this PR