Add missing krb5 devel dependency when building packages

.pkgr.yml

@@ -4,6 +4,7 @@ before_precompile: ./bin/pkgr_before_precompile.sh
 targets:
   debian-7: &wheezy
     build_dependencies:
+      - libkrb5-dev
       - libicu-dev
       - cmake
       - pkg-config
@@ -14,6 +15,7 @@ targets:
   ubuntu-12.04: *wheezy
   ubuntu-14.04:
     build_dependencies:
+      - libkrb5-dev
       - libicu-dev
       - cmake
       - pkg-config
@@ -23,6 +25,7 @@ targets:
       - git
   centos-6:
     build_dependencies:
+      - krb5-devel
       - libicu-devel
       - cmake
       - pkgconfig