Added targeted request option & test

- Updated README
- Added --match option to argumentparser
- Added help for targeted requests
Included architecture in Software-ID
Changed platform strings to be x86_64 or i686

Fixes tnc-ba/swidGenerator#10
Merge pull request #10 from tnc-ba/issue10-architecture-string

HW Architecture in SWID tags and softwareIDs
Added setup.py to make the SWID generator easily installable

The swid_generator script can now be installed to your local PYTHONPATH
with ::

    python setup.py install

To install only symlinks to the sourcefiles (which means that code
changes are immediately reflected in the installation), use ::

    pip install -e .

Refs tnc-ba/strongTNC#40.