Replaced references to base profile / BaseProfile.

  Now that Profile is it's own data object, no need to complicate things trying
  to distinguish between base profile and other profiles. Just call it profile.

 	modified:   Profile.php
Updated ProfileInstaller::setInstallCallbacks, ::setUpNewHookInvocationsForState.

  ProfileInstaller shouldn't need to know about or invoke methods provided by
  Profile::profile_utility.
Added hook_install to ProfileUtility::getSupportedHooks.

  Handle hook_install consistently with the rest of the hooks.
Fixes PHP warnings.

  This was attempting to track invocations for supported hooks even if they were
  not implemented.
Updated property documentation.

 	modified:   Profile.php
Updated Profile property name and corresponding function.

  ProfileUtility::findHookInProfile -> ::findHookImplementationsInIncludedProfiles
  Profile::hook_implementations     -> ::included_hook_implementations