Issue title: Unable to add new Environment variable.
 Issue body: Not able to add new environment variable.
Clicking on submit does not do anything. 
I took latest version of POSTMan today.

 Comments: 
 Comment 0: Which browser/OS version are you on?

 Comment 1: Thanks Abhinav,
I am using Mac OS.
I re-installed Chrome and was able to work with POSTMan.

But I suspect other extensions I had in my chrome, that might caused problem.
I had Flash blocker and Ad blocker.

 Comment 2: Phew. Closing this then. 

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