Add user agent header

[VishalMCF]

resolves #104

[VishalMCF]

@Cliftonz Can you please review?

[unicodeveloper]

@mayorJAY Please review

[mayorJAY]

This implementation would give us the name and version of the client app instead of the info of this SDK. We need to revert and revisit the implementation @Cliftonz @unicodeveloper @VishalMCF

[VishalMCF]

@mayorJAY @Cliftonz @unicodeveloper I was thinking of an approach where I hardcode the version in the RetryHandlerClass. Name as you said can be hardcoded. I can write a test function that always checks if the version is the same as what we have in the pom.xml file. What do you say? That way don't have to risk reading the file during runtime.

[mayorJAY]

@mayorJAY @Cliftonz @unicodeveloper I was thinking of an approach where I hardcode the version in the RetryHandlerClass. Name as you said can be hardcoded. I can write a test function that always checks if the version is the same as what we have in the pom.xml file. What do you say? That way don't have to risk reading the file during runtime.

I don't think we should hardcode the version, that would mean updating the header every time there is a version change. If we modify the code based on my suggestions, we'd get what we need

[VishalMCF]

@mayorJAY cool, I will raise a new PR as per your suggestions