pgem_reload overwrites PATH changes that were made after loading ProfileGem

[dimo414]

Due to this line, if PATH is modified after loading ProfileGem the update will be lost after reloading. This is arguably WAI since ProfileGem is expected to manage all path changes after being loaded (via pg::add_path in individual gems) but the resulting behavior of paths being dropped is not great.

At a minimum pgem_reload could detect when the PATH has been changed since load.sh completed and log a warning.