Sample Upload Issues

We have come across a number of issues and inconsistencies with uploading Samples, and these commits attempt to address them.
- Input in the Method form field was always ignored, while Reference was ignored in some cases
- The "Upload Child Sample" button was previously changed to "Upload Related Sample". This fits better with the "Related_To" relationships that is formed. I changed "parent" to "related" in other places where a "Related_To" relationship was formed for consistency.
- In some cases, Sources were inherited when uploading a "related" Sample and this would eventually lead to a mess of Sources that didn't always fit the Sample being uploaded. We are of the opinion that a "related" Sample should not automatically always inherit Sources as the user can always follow the relationship back to view them.
- In some cases, Campaigns were inherited by "related" Samples. We feel that this makes sense for all "related" Sample uploads. This is similar to issue #14.
- When uploading a "related" Sample, the "Related MD5" field would be ignored, so I hid that field in those cases.
- Adding a Sample to an email had its own form for what appeared to be no good reason. I removed it so we could consistently use the "new-sample" form.

Hopefully the rest make sense without further explanation. Please let me know if you'd like additional details on the rationale behind the fixes/changes.