Passive SONAR instruction

[viron11111]

The Wiki is missing a write up on how to use the passive SONAR. Readme of passive SONAR has legacy command of: "rosrun mil_passive_sonar sonar.launch."

[sentree]

The overhaul of the passive sonar system was put on hold after there were hardware issues with Jake's board and there were plans for a new board to be created. Now that we have a functional way to interact with the old Paul board, @DSsoto will complete work on #17 and I will write an interface to make it compatible with that board. Until this is complete, I recommend checking out an older version of the SubjuGator repository to get a functional sonar package as follows:

git clone https://github.com/uf-mil/SubjuGator
cd SubjuGator
git reset --hard 0089e68b9f48b96af9c3821f356e3a487841e87e