Newer versions of cmake do not set install_name, so we need to do it
ourselves.
FindDPDK module did not properly handle version range before, this
change fixes this.
Also made boost a system dependency to suppress compiler warnings from
it.

Some minor formatting, spaces etc

This change fixes a few annoying compiler warnings. Mostly, those
are related to unused variables which are simply suppressed.
Also fixes a missing virtual destructor which could have resulted
in memory issues.

Implement n-repeat option in tx_samples_from_file example to repeat a
transmission for a specified amount of times

- Fixed sigint handler condition
- Restored previous delay behavior
- Added explanatory command for boost system header inclusion