Change the brandMotto of nightly builds. After all, geeks can also do magic!

im/branding/nightly/locales/en-US/brand.dtd

@@ -2,5 +2,5 @@
 
 <!ENTITY  brandShortName        "Instantbird">
 <!ENTITY  brandFullName         "Instantbird - Nightly">
-<!ENTITY  brandMotto            "'Cause witches can also type!">
+<!ENTITY  brandMotto            "'Cause geeks can also do magic!">
 <!ENTITY  vendorShortName       "Instantbird">