Added Integral Calc

[IshaanShettigar]

Issue Id you have worked upon -

96

Briefly explain your program logic -

There is no function in mathjs that lets you do this directly so I had to write my own. Basically I take in an input like 3x^2 + 2x and then it gets split into an array like ["3x^2", "+", "2x]. In this process I do check with many regex's to make sure that the user has entered the correct value. After this I just integrate it using the polynomial integration formula that we all know.

Screenshots(Attach 2 screenshots of your own input and output) -

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• [x] My code follows the guidelines of this project.
  

• [x] I have performed a self-review of my own code.
  

• [x] I have commented my code.
  

• [x] My code gives the correct output.
  

• [x] I affirm that I strictly follow contributing guidelines and code of conduct.

[SarthakKeshari]

Congratulations 🎉 @IshaanShettigar on your contribution. Thanks for adding value to this repository. 😊

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[SarthakKeshari]

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