…splaying the text from stderr file generated during submission in terminal

Fix for enhancement#1003: Google Code-in Task to add a command for displaying the text from stderr file generated during submission in terminal.

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This is for Google Code-in Task. Google Code-in Task to add a command for displaying the text from stderr file generated during submission in terminal. I followed with the same feedback provided by mentor Mr. Kartik Verma for the task to display stdout file from the remote host, i.e. where the EvalAI has stored the file. request is to make a API call to EvalAI server to get submission details.

Following are the modifications:

modified/added :
modified: main.py to include the submission_error command
modiifed: evalai/utils/submissions.py to display the stderror message
added: submission_error.py file to support the above functionality.

Added the stderr function in nested under submission command as suggested by Mr. Karthik Verma. Also reverted the changes to main.py and removed the new file submission_error.py

Fixed failing build on PR#256. Google code-in task #1003

This reverts commit d61f216.

Fixed faile PR#256 for google codein task#1003

PR#256 - Adding Test case for the stderr file output to terminal window. This is for Google code-in task #1003

fixed code coverage for stderr file and updated the exception to common error.

updated version to fix code coverage to improve 0.9%. Removed exception since it retrieve straight forward URL from s3 bucket. and moreover we are priniting the error message to the terminal and hence removed the exception.