Address Issues 127 & 126

[yregaieg]

Issue 127 is actually caused by the fact that old forms were never cleaned up, this PR provide extra cleaning A- Whenever uploader-plus is invoked for an upload B- Between multiple files upload after a metadata form has been processed.

[yregaieg]

@douglascrp 32e0842 is meant to address #126 (if my understanding of the issue is correct).
When I first introduced the length restriction for the form, I only tested it with date-formcontrol on the top of the form which contributed to me easily missing the issue.

[douglascrp]

I think the code block could be converted into a function into the uploader-plus-mixin.js, and then the 4 copies could be replaced by the function being called.
As the SoftwareLoop.UploaderPlusMixin is merged into the other 3 files, the function would be available for them too.

What do you think?

[yregaieg]

@douglascrp couldn't agree more !

[douglascrp]

@yregaieg PR merged, but I am going to execute the change I commented before.
Thank you for your help.

[douglascrp]

@yregaieg Dude, I have just finished the changes we were talking about.
Would you mind trying this new version in your test environment?
You can find my changes at https://github.com/douglascrp/uploader-plus/tree/issue-127-B