I18n: improve unit extraction regex

There were two issues with the unit extraction regex:
- it didn't take the inches, feet, arcminutes and arcseconds symbols
into accounts, which aren’t letters but ' and ";
- some units have more than one B_UNIT_DEF_* flag.

This allows extracting feet, inches, square millimeters, cubic
millimeters, arcminutes, and arcseconds.

Reviewed By: mont29

Differential Revision: https://developer.blender.org/D16144

release/scripts/modules/bl_i18n_utils/settings.py

@@ -260,9 +260,9 @@ PYGETTEXT_KEYWORDS = (() +
     # NOTE: regex is a bit more complex than it would need too. Since the actual
     # identifier (`B_UNIT_DEF_`) is at the end, if it's simpler/too general it
     # becomes extremely slow to process some (unrelated) source files.
-    ((r"\{(?:(?:\s*\"[^\"',]+\"\s*,)|(?:\s*NULL\s*,)){4}\s*" +
+    ((r"\{(?:(?:\s*\"[^\",]+\"\s*,)|(?:\s*\"\\\"\",)|(?:\s*NULL\s*,)){4}\s*" +
       _msg_re + r"\s*,(?:(?:\s*\"[^\"',]+\"\s*,)|(?:\s*NULL\s*,))(?:[^,]+,){2}"
-      + "\s*B_UNIT_DEF_[_A-Z]+\s*\}"),) +
+      + "(?:\|?\s*B_UNIT_DEF_[_A-Z]+\s*)+\}"),) +
 
     tuple((r"{}\(\s*" + _msg_re + r"\s*,\s*(?:" +
            r"\s*,\s*)?(?:".join(_ctxt_re_gen(i) for i in range(PYGETTEXT_MAX_MULTI_CTXT)) + r")?\s*\)").format(it)