Generate the UTF-8 bytes with leading zeros (%02x instead of just %x)

Avoids gratuitous changes omitting leading zeros where nothing
really changed.
Add EastEasianWidth.txt from Unicode 7.0.0
Remove commented out debug code
Use common Python indentation of 4 spaces per indentation level

Style Guide for Python Code:

https://www.python.org/dev/peps/pep-0008/#indentation
Add my name to contributors
Fix typos in usage message
Simplify parsing of the UTF-8 file
Store integers as keys in the width_dictionary

To make the dictionary sort correctly numerically.
Changes the output of the report like this:

$ diff  -u report-utf8.orig report-utf8.new
--- report-utf8.orig    2014-11-19 15:25:38.941885123 +0100
+++ report-utf8.new     2014-11-19 15:54:14.059889316 +0100
@@ -4,6 +4,7 @@

 Report on WIDTH:
 Total missing characters in newly generated WIDTH:  330
+0x06de : 0
 0x1160 : 0
 0x1161 : 0
 0x1162 : 0
@@ -312,7 +313,6 @@
 0x4dfd : 2
 0x4dfe : 2
 0x4dff : 2
-0x6de : 0
 0xa48d : 2
 0xa48e : 2
 0xa48f : 2
Slight code simplification
Use argparse for easier and more flexible command line parsing
Add code to optionally show added characters