Change colour space

[aakriti1318]

Hey, GSSoC`21 participant.
I would like to work on this issue.

[Dhanush2612]

Hi I am participant @GSSOC 21, can you assign me this issue?

[Ashishsingh619]

Hi, I'm a GSSoC`21 participant and want to contribute to this. I have good knowledge about this topic and want to apply my knowledge to practice, So can you please assign me this issue
@geekquad sir and @kritikaparmar-programmer maam

[geekquad]

Assigning Change colour space BGR ↔ Gray to @aakriti1318.
Assigning Change colour space BGR ↔ HSV to @Dhanush2612.

[Dhanush2612]

@geekquad I have completed my part and done with PR #88.

[aakriti1318]

@geekquad I have completed my part as well BGR2GRAY #89. Review this.