createBranch - whether the branch should be created if it does not already
exist
setForce
public void setForce(boolean force)
Parameters:
force - if true and the branch with the given name
already exists, the start-point of an existing branch will be
set to a new start-point; if false, the existing branch will
not be changed
execute
public void execute()
throws org.apache.tools.ant.BuildException