DATACMNS-325 - Open up lower boundary of Slf4j to 1.6.4 in MANIFEST.MF.

This change was introduced to ease the upgrade of STS to recent Spring Data Commons versions, originally introduced to enable Spring 4 compatibility (see DATACMNS-324).

template.mf

@@ -27,7 +27,7 @@ Import-Template:
  org.springframework.web.*;version="${spring30:[=.=.=,+1.1.0)}";resolution:=optional,
  org.aopalliance.*;version="[1.0.0, 2.0.0)";resolution:=optional,
  org.joda.time.*;version="${jodatime:[=.=.=,+1.0.0)}";resolution:=optional,
- org.slf4j.*;version="${slf4j:[=.=.=,+1.0.0)}",
+ org.slf4j.*;version="[1.6.4,2.0.0)",
  javax.servlet.*;version="[2.5.0, 4.0.0)";resolution:=optional,
  org.w3c.dom.*;version="0"
 DynamicImport-Package: *