Feature/implement generic add

[Anshuman71]

Implement the add(Object) function from Moment and fix #1427

Add 2 hours, 15 minutes and 30 seconds to 10 July 2014 12:45:00;

var result = add(new Date(2014, 6, 10, 12, 45, 0), { minutes: 15, hours: 2, seconds: 30 });

result: Thu Jul 10 2014 15:00:30

Supports adding

{
    hours: number,
    years: number,
    days: number,
    quarters: number,
    weeks: number,
    months: number,
    minutes: number,
    seconds: number
} 

combined in a single call

[Anshuman71]

@leshakoss @alaskaa @dkozickis can you please review this PR

[dkozickis]

Thank you for your PR @Anshuman71!
Please go through the comments.

[leshakoss]

The function is good, but as of now in a bundle it would be huge: it includes, for example, the impossible condition if (arguments.length < 2) ... 8 times.

Please optimize the function by copying and pasting the logic inside all of addX functions into this one, optimizing where possible (for example you can add ms, seconds, minutes and hours on the same line because all of these are milliseconds multiplied by some constant). After that, the function should be able to do everything addX do, but without importing them.

[Anshuman71]

The function is good, but as of now in a bundle it would be huge: it includes, for example, the impossible condition if (arguments.length < 2) ... 8 times.

Please optimize the function by copying and pasting the logic inside all of addX functions into this one, optimizing where possible (for example you can add ms, seconds, minutes and hours on the same line because all of these are milliseconds multiplied by some constant). After that, the function should be able to do everything addX do, but without importing them.

Thankyou, I will surely optimize the code with the above advise

[kossnocorp]

@Anshuman71 hey, I love the PR, but I see that I've removed the repo, and now I can't resolve the conflicts and clean up the code. I'll appreciate it if you can push it again or send me the patch file. Thanks!

[Anshuman71]

Hey @kossnocorp, thanks for your feedback. I moved this to #1581 . Please look into and let me know if need any changes.