(AIX) Convert rpm comparisons (regex -> semver)

Prior to this commit, the RPM package provider was using regular
expressions for comparing versions of the `rpm` utility. The regex
method, while functional, is not exactly readable nor does the regex
hold up once `rpm` hits version 10. This commit uses SemVer (even though
the `rpm` versions are *semantically* versioned, the SemVer library
already exists and can easily handle version comparisons) for checking
the specific cases of `rpm` versions < 4.1 and < 4.0.2.

Sprintly: fixes item:195