Export to PDF

[sg]

Two comments on the Export to PDF button:

(1) It silently writes the file even when it already exists -- clobbering existing files

(2) The box for the file name is labeled "Export folder:" as opposed to export file.  If I used a folder name, would it silently clobber my
whole folder?

[fmk]

1. we will have the standard dialog pop up if file exists. jira entered
2. it does not clobber dir, but does nothing either. we will create a pop up and inform user of fact.

[fmk]

code modified.  will be in next release (anything greater than v1.0.0)