Updating ease of usage of nightly_build.py

Created by: Thomas-J-Kidd

Two main changes:

Change 1 nightly_build.py has a new directory structure and default arguments for running the script.

The arguments are:

'--path',default = "nightly"
'--repository',default = "https://github.com/openhwgroup/cvw"
'--target', default = "all"
'--send_email',default = "yes"

The new directory structure is that by default the new repositories and results will be in the following: ~/nightly/<date>/cvw ~/nightly/<date>/results ~/nightly/<date>/logs

The logger class creates a really readable log file in ~/nightly/<date>/logs called nightly_build.log. Other log files in there are from making and running the tests.

Change 2 The wrapper_nightly_build.sh is modified to source a setup.sh script and get rid of the log directories since that causes issues with running the tests. Getting rid of the logs for running the commands is okay, in my opinion, because of the logger class that documents the issues caught in the program. This logging still needs to improve with added try and except statements but its a move in the right direction for readability and accessibility of the log file. Also now there is a log folder specifically for each day instead of just one.