Improvements for some English strings

Running through the current de.po file I noticed some strings that may need some improvement and/or correction:

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Save changes to the panorama before closing?

-> Save changes to the project (file) before closing?

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in Preferences -> Filenames

The line
 %directory - folder name (based on first image file)\n

should IMHO get an improved description like this:
 %directory - folder name (based on location of first image file)\n

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Save changes to the panorama before opening an other project?
If you load an other project without saving, your changes since your last save will be discarded.

-> instead of "panorama" we should use "project file" instead
-> "another" instead of "an other"
-> you without 'r' in "since you last saved the file"

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One "Tip of the Day" should get some addition

Current string:
Rotating the camera around the entrance pupil (sometimes also called "nodal point") avoids parallax errors and makes panorama creation a lot easier.

my proposal:
Rotating the camera around the entrance pupil of the lens (sometimes incorrectly called "nodal point") avoids parallax errors and makes panorama creation a lot easier. The Panotools wiki <http://wiki.panotools.org/NPP> helps you to find the correct point for your lens.

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There is a typo (BE instead of AE) somewhere in the .po file:

colour
-> color

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Another typo (plural needed in this case):

Only use control points between image selected in preview window.
-> images

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And where is the string "Feature descriptor:" used? I suspect the german translation is wrong or inaccurate but cannot identify where it is shown in the GUI.