Missing System.Management reference

Added missing System.Management reference in the project
Further commits for IIS support

- Now handling service state set to Manual
- Restarting the scvhost at the end of the collection to reset the
environmental variables
Wait 3 seconds before trying a start

- Now handles the issue with the scvhost not being restarted by the
services.exe process
Merge branch 'master' of https://github.com/AndiVlad/opencover into AndiVlad-master
Merge branch 'AndiVlad-master'
Merge branch 'master' of github.com:sawilde/opencover