ctdb-tools: Improve printing of multi-line event script output

ctdb-tools: Improve printing of multi-line event script output

Multi-line output currently prints like this:

  OUTPUT: aaa
bbb
ccc

This is less beautiful than it could be.

Instead, print multi-line output with no inlining and each line
indented:

  OUTPUT:
    aaa
    bbb
    ccc

However, continue to inline single line output:

  OUTPUT: foo

Signed-off-by: Martin Schwenke <mschwenke@ddn.com>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>