jesred shouldn't depend on squid

[Karl-Philipp Richter]

It shouldn't be necessary that `jesred` depends on `squid` because it should be usable with other source/non-package installations of `squid` as well. A meta package which depends on `squid` and `jesred` could be introduced.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: jesred 1.2pl1-19
Uname: Linux 4.2.5-040205-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
Date: Fri Feb 26 13:14:06 2016
InstallationDate: Installed on 2015-04-20 (311 days ago)
InstallationMedia: Ubuntu-Server 14.10 "Utopic Unicorn" - Release amd64 (20141022.2)
ProcEnviron:
 TERM=screen
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: jesred
UpgradeStatus: Upgraded to wily on 2015-10-26 (123 days ago)