Add upper Shellfu version limit

packaging/debian/control

 Build-Depends:
  debhelper (>= 9),
  shellfu (>= 0.10),
+ shellfu (<< 0.11),
  shellfu-bash,
  shellfu-bash-inigrep,
  shellfu-bash-pretty,
 Architecture: all
 Depends:
  shellfu (>= 0.10),
+ shellfu (<< 0.11),
  shellfu-bash,
  shellfu-bash-inigrep,
  shellfu-bash-pretty,

packaging/template.spec

 BuildArch:	noarch
 BuildRequires:	coreutils
 BuildRequires:	shellfu => 0.10
+BuildRequires:	shellfu < 0.11
 BuildRequires:	shellfu-bash-inigrep
 BuildRequires:	shellfu-bash-pretty
 BuildRequires:	shellfu-sh-exit
 Requires:	shellfu => 0.10
+Requires:	shellfu < 0.11
 Requires:	shellfu-bash
 Requires:	shellfu-bash-inigrep
 Requires:	shellfu-bash-pretty