Removing a custom part from a bin does not fully remove it

What steps will reproduce the problem?
1. Import a new custom part into a bin
2. Right click on the new part and select 'Remove part'
3. Import the same part again

Attach your sketch file and/or custom part files to the bug report.

What is the expected output? What do you see instead?

Fritzing should import the new part a second time.  Instead it reports "There 
is already a part with id 'XYZ' loaded into Fritzing."

What version of Fritzing are you using? On what operating system?

0.9.0b - Ubuntu 2014.04 i386

Please provide any additional information below.

Saving the bin after removing the part does not fix the problem.

Quitting and restarting Fritzing does clear the problem.

This is a real pain when testing new parts as you need to restart Fritzing 
every time you want to modify a custom part.

Original issue reported on code.google.com by d...@cording.id.au on 18 Aug 2014 at 1:15

anxb26 / fritzing

Removing a custom part from a bin does not fully remove it #2987