Added ability to use package kit filters with the searchPackage()
function.  See:
http://www.packagekit.org/gtk-doc/introduction-ideas-filters.html
Demo of using linus 'find' command with the node packagekit add-on.
Added capability to update packages using the packagekit node
add-on -- added method updatePackage().  Updated unit tests as
appropriate.
Added 'type' option to find command to search only for regular
files, and, generally, improved the output to make it more apparent
what was found.  Removed commented out code (stderr output).
Added searchFiles() that, given a path(s) to a file, calls
packagekit's "search files" function that returns package
package information on the path(s).
Also added utility handleFiltersArgumen() that is shared by
searchFiles() and searchPackage().
Modified the find + search-package-kit demo (aka findSearchPk.js)
to make use of the new searchFiles() function of the packagekit
add-on.
Fixed bug in call to searchFiles().
It now bases the search on what the "find" command returned, not on the input to the find command.
Also, improved the name of the array containing the paths found by the find command.
Merge pull request #3 from klown/packagekitBridgeFilters

Added ability to use filters with searchPackage() function.