Exclude jline 0.9.94 dependency from curator

- The subproject spring-xd-dirt's compile dependency Curator 2.4.0 has jline 0.9.94
as a transitive dependency.
Currently, spring-xd-shell's spring-shell has jline-2.11 as the dependency.
Since, spring-xd-shell has spring-xd-dirt as "testCompile" dependency, there is
a conflict using spring-xd-shell only from within IDE.

The spring-xd-shell project has "testCompile" dependency on spring-xd-dirt