Adding locks around some collection loops

* Issue #510 - dictionary changed size during iteration
When loading an object initialize *interface fields with defaults

Issue #509 - Sync fails to render DNS files following a replicate

Also fixes an issue where the logger object is not set when calling
the api.sync() function from the replicate module, resulting in a
stack trace
Merge pull request #517 from jimi1283/issue_509

When loading an object initialize *interface fields with defaults
Merge pull request #518 from jimi1283/issue_510

Adding locks around some collection loops
Fixing a silly goof in not using self.lock
Merge pull request #519 from jimi1283/issue_510

Fixing a silly goof in not using self.lock
Adding in logging of an exception generated by a kickstart parse error
Merge pull request #520 from jimi1283/miscimprovements

Adding in logging of an exception generated by a kickstart parse error
Changing spec to require Django14, which supercedes Django in EPEL
Merge pull request #521 from jimi1283/miscimprovements

Changing spec to require Django14, which supercedes Django in EPEL
Rolling back that Django change
Not sure if we want to pull the trigger on that yet, plus it looks
like it'll need to be selective based on the distro as Fedora still
calls the package Django and has no Django14 package
Merge pull request #522 from jimi1283/miscimprovements

Rolling back that Django change
Limit splitting of interface names to one dash

Issue #511 - interfaces with - in the name cause exception
Merge pull request #523 from jimi1283/issue_511

Limit splitting of interface names to one dash
Create sylink in links/ for distros during "cobbler distro add"

Issue #513 - "cobbler distro add" does not add a link to the distro
in the links directory.
Merge pull request #524 from jimi1283/issue_513

Create sylink in links/ for distros during "cobbler distro add"
Enforce the use of --interface when no interfaces are defined

Issue #526 - cobbler system add creates broken record when used
with --dns-name and no interface
Merge pull request #527 from jimi1283/issue_526

Enforce the use of --interface when no interfaces are defined
Fix http check on SUSE platform. Addresses bnc#828453

On SUSE platform Apache's binary is called 'httpd2'.

This addresses one of the issues reported by bnc#828453.
Merge pull request #531 from flavio/fix_http_check_on_suse_platform

Fix http check on SUSE platform. Addresses bnc#828453