do not fail on repeated enabling/disabling of sources -- v3

[satta]

Previous PR: #85

Makes sure to update parameters when re-enabling a source, printing a log message for each changed parameter.

• I have read the contributing guide lines at
  https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Contributing
• I have signed the Open Information Security Foundation
  contribution agreement at
  https://suricata-ids.org/about/contribution-agreement/
• I have updated the user guide (in doc/) to reflect the
  changes made

See ticket 2728.

Describe changes:

• Use descriptive variable name.
• Restructure code flow to reduce nesting.

[shivan1b]

LGTM. Thanks!

[jasonish]

Looks good. @shivan1b Can you merge this into master? We should probably get it into the next point release as it seems to be a running concern for a couple users now.

[shivan1b]

@jasonish sure,

[shivan1b]

Merged into master.