Image extraction fixes and minor improvements

This release fixes a number of problems when extracting CMYK indexed images.

New features:

• Save file now opens in the same directory of the first input file
• Remembers last saved filename (in the same execution)

Slightly better UI resizing and last file enhancements

Now the buttons do not expand when resizing the window, leaving more space for the file and page names.

The program now picks the directory from the first file in the file list. When saving again (if not clearing the file list), the saved file's name is remembered.

The file is now substantially bigger due to bumping PyQt's version to 5.

v1.0

This is the first release of PyPDFTK. It is in fully working condition. All you should need to use it on Windows is the attached exe.

If you find any problems, report it in the Issues tab.