Bug 24734: Fix paths in LangInstaller.pm for JS files

Bug 24734: Fix paths in LangInstaller.pm for JS files

Use intrahtdocs and opachtdocs in order to get the correct paths for all
kind of installations

Test plan:
1. With a dev install, run ./translator create/update/install xx-XX and
   verify that there is no error message
2. With a standard install, run ./translator create/update/install xx-XX
   and verify that there is no error message

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Tested for dev/single/standard installs, no errors,
just a (normal) warn from po2json.

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Joy Nelson <joy@bywatersolutions.com>