Added link validator.

[amolkahat]

• It will check link is valid or not.
• If link is like https://<hostname>:<port> then it should mark it as skip.

Signed-off-by: Amol Kahat amolkahat@gmail.com

Fixes #12

[raukadah]

Please add some test data in tests folder so that it can be validated

[digitronik]

@amolkahat thanks for PR... please have look on pre-commit checks for more info Analysis (git diff) block.