add support for a test to verify Solaris IPS packages

[djhaynes]

At OVAL Developer Days, a request was made to investigate a test that would be able to verify installed Solaris IPS packages. Please see the OVAL Developer Days minutes for more information.

http://oval.mitre.org/community/docs/Developer_Days_2013_OVAL_Session_Minutes.pdf

The "pkg verify" command may also help in understanding the types of information that can be collected. More information can be found in the pkg man page.

http://docs.oracle.com/cd/E23824_01/html/E21796/pkg-1.html