hg-fast-export: add option to track remote branches under a custom namespace

Add -o, --origin <name> to allow user to set a namespace used
when importing remote branches.

Signed-off-by: Fabrizio Chiarello <ponch@autistici.org>

hg-fast-export.sh

@@ -12,7 +12,7 @@ SFX_STATE="state"
 QUIET=""
 PYTHON=${PYTHON:-python}
 
-USAGE="[--quiet] [-r <repo>] [-m <max>] [-s] [-A <file>] [-M <branch_name>]"
+USAGE="[--quiet] [-r <repo>] [-m <max>] [-s] [-A <file>] [-M <name>] [-o <name>]"
 LONG_USAGE="Import hg repository <repo> up to either tip or <max>
 If <repo> is omitted, use last hg repository as obtained from state file,
 GIT_DIR/$PFX-$SFX_STATE by default.
@@ -26,7 +26,8 @@ Options:
 	-A	Read author map from file
 		(Same as in git-svnimport(1) and git-cvsimport(1))
 	-r	Mercurial repository to import
-        -M      Set the default branch name
+        -M      Set the default branch name (default to 'master')
+        -o      Use <name> as branch namespace to track upstream (eg 'origin')
 "
 
 . "$(git --exec-path)/git-sh-setup"