Move default fonts to new crate epaint_default_fonts (#4853)

This allows license checking tools to omit the OFL and UFL licenses when
`default_fonts` are turned off.

There was some discussion of versioning on the original issue; I have
chosen to label this version as `0.28.1` to match the other crates.
Happy to adjust the version as needed.

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* Closes <https://github.com/emilk/egui/issues/2321>
* [X] I have followed the instructions in the PR template

---------

Co-authored-by: Alex Pinkus <pinkus@amazon.com>

crates/epaint_default_fonts/fonts/list_fonts.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+from fontTools.ttLib import TTFont
+from fontTools.unicode import Unicode
+from itertools import chain
+import sys
+
+ttf = TTFont(sys.argv[1], 0, verbose=0, allowVID=0,
+             ignoreDecompileErrors=True,
+             fontNumber=-1)
+
+chars = chain.from_iterable([y + (Unicode[y[0]],)
+                             for y in x.cmap.items()] for x in ttf["cmap"].tables)
+
+
+all_codepoints = {}
+
+for entry in chars:
+    codepoint = entry[0]
+    short_name = entry[1]
+    long_name = entry[2].lower()
+    if False:
+        print(f'(0x{codepoint:02X}, "{short_name}", "{long_name}"),')
+    else:
+        name = short_name if long_name == "????" else long_name
+        # print(f'(0x{codepoint:02X}, "{name}"),')
+        all_codepoints[codepoint] = name
+
+for codepoint in sorted(all_codepoints.keys()):
+    name = all_codepoints[codepoint]
+    print(f'(0x{codepoint:02X}, \'{chr(codepoint)}\', "{name}"),')
+
+ttf.close()