Fixes #3445 : Clean classes expression in rpmPackageInstallation
Refs #3454 - Factorize use of execresult in site.st and fusionAgent.st
Refs #3454 - Remove use of useless classes
Refs #3454 - Fix typo and format
Fixes #3446 : read data from an external file for rpmPackageInstallation
Refs #3446 : use readstringarrayidx rather than readstringarray
Merge pull request #83 from ncharles/ust_3444/dev/3446_read_data_from_external_file

Ust 3444/dev/3446 read data from external file
Merge pull request #86 from nperron/ust_3453/dev/3454_factorize_use_of_execresult

Refs #3454 - Factorize use of execresult in site.st and fusionAgent.st
Revert "Merge pull request #83 from ncharles/ust_3444/dev/3446_read_data_from_external_file"

This reverts commit 8b166a669efe8a95d58a3d63ed460fad93032f8b, reversing
changes made to 56d4a6e5f1197b56f3302829bd08f15fc06c8e31.
Merging 2.3 into 2.4, and checking refs #3454