The new boolean 'flush_line' option in the filelog section of
strongswan.conf specifies if log messages should be flushed to the given
file for each new line.
Makes refactorings easier."
This reverts commit e91b116a622bbfb20cd66268ca4cb91d620984ad. Missed to
notice commit 89bf11d204cb934ea9109aa077c8514515d538f6.