Reports: Added logic to download bhav copy and market activity reports.

[jitendravarma]

Added logic to process

1. Market activity report for a given date and returns raw text (since ma report has lot many inner tables). So, I have let user decide what they want to do with raw content
2. Added logic to download bhav copy zip

Updated Readme.

How was it tested?
Ran locally for multiple use cases.

Breaking changes: No.

[pratik141]

Please add test case to validate o/p is comming as expected if possible
please run Pylint also

[jitendravarma]

Please add test case to validate o/p is comming as expected if possible please run Pylint also

Updated test cases.

[jitendravarma]

Have updated logic for fake headers, as it a must for this.

[jitendravarma]

Fixed test cases and modified bhav copy download logic now supports df or json.