userdiff: add support for Fountain documents

Add support for Fountain, a plain text screenplay format.  Git
facilitates not just programming specifically, but creative writing
in general, so it makes sense to also support other plain text
documents besides source code.

In the structure of a screenplay specifically, scenes are roughly
analogous to functions, in the sense that it makes your job easier
if you can see which ones were changed in a given range of patches.

More information about the Fountain format can be found on its
official website, at http://fountain.io .

Signed-off-by: Zoë Blade <zoe@bytenoise.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/userdiff.c b/userdiff.c
index 2ccbee5..6bf2505 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -35,6 +35,8 @@ IPATTERN("fortran",
 	  * they would have been matched above as a variable anyway. */
 	 "|[-+]?[0-9.]+([AaIiDdEeFfLlTtXx][Ss]?[-+]?[0-9.]*)?(_[a-zA-Z0-9][a-zA-Z0-9_]*)?"
 	 "|//|\\*\\*|::|[/<>=]="),
+IPATTERN("fountain", "^((\\.[^.]|(int|ext|est|int\\.?/ext|i/e)[. ]).*)$",
+	 "[^ \t-]+"),
 PATTERNS("html", "^[ \t]*(<[Hh][1-6][ \t].*>.*)$",
 	 "[^<>= \t]+"),
 PATTERNS("java",