implement If-diff script

[narekhovhannisyan]

Types of changes

• Enhancement (project structure, spelling, grammar, formatting)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

A description of the changes proposed in the Pull Request

• Implement if-diff script.

[jmcook1186]

if-diff is returning a failure response based on execution.command which is supposed to be a ignored field.
Please ignore all information in execution EXCEPT status and error.

[narekhovhannisyan]

@jmcook1186 it will be covered with #706

[jmcook1186]

sgtm - I checked out locally and verified that:

• two identical files return success response
• two non-matching files returned failure response and expected diff report
• piping from ie to if-diff worked as expected

[jmcook1186]

Must fix #734
and #733 from QA review
before this can be merged

[MariamKhalatova]

@narekhovhannisyan In case of using wildcard , the '*' is accepted as a value, and an error is received.

Files do not match!
tree.children.child-0.outputs[0].cpu/utilization
source: *
target: 20

[MariamKhalatova]

@narekhovhannisyan When the quantity of array members doesn't match in source and target files, then the following error is received.
Expected result: Should show the first missing array member

Files do not match!
tree.children.child-0.outputs
source: [object Object]
target: [object Object],[object Object],[object Object]

[narekhovhannisyan]

fixes #733
fixes #734

[jmcook1186]

sgtm!