Merge branch 'pe/doc-email-env-is-trumped-by-config'

In the precedence order, the environment variable $EMAIL comes
between the built-in default (i.e. taking value by asking the
system's gethostname() etc.) and the user.email configuration
variable; the documentation implied that it is stronger than the
configuration like $GIT_COMMITTER_EMAIL is, which is wrong.

* pe/doc-email-env-is-trumped-by-config:
  git-commit-tree(1): correct description of defaults

Documentation/git-commit-tree.txt

@@ -72,13 +72,13 @@ if set:
 	GIT_COMMITTER_NAME
 	GIT_COMMITTER_EMAIL
 	GIT_COMMITTER_DATE
-	EMAIL
 
 (nb "<", ">" and "\n"s are stripped)
 
 In case (some of) these environment variables are not set, the information
 is taken from the configuration items user.name and user.email, or, if not
-present, system user name and the hostname used for outgoing mail (taken
+present, the environment variable EMAIL, or, if that is not set,
+system user name and the hostname used for outgoing mail (taken
 from `/etc/mailname` and falling back to the fully qualified hostname when
 that file does not exist).