Add Bridge Tests to ethportal-peertest

[KolbyML]

Here is a link to the context #1781 (review)

[Arya-A-Nair]

Would like to work on it

[Arya-A-Nair]

@KolbyML Are there any specific cases that you would want me to cover?

[Arya-A-Nair]

@KolbyML can you help me understand what cases do i have to integrate?