[latexila] Add Latexmk or Rubber as optional requirements

[SÃbastien Wilmet <swilmet src gnome org>]

commit 45a49fda3fed027adc78107df71ec25e618d9e3f
Author: SÃbastien Wilmet <swilmet src gnome org>
Date:   Mon Aug 29 03:00:51 2011 +0200

    Add Latexmk or Rubber as optional requirements

 INSTALL |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/INSTALL b/INSTALL
index 9100445..4e36093 100644
--- a/INSTALL
+++ b/INSTALL
@@ -17,6 +17,9 @@ Vala 0.12.x >= 0.12.1 (may be optional)
 If you are installing LaTeXila from a tarball, you don't have to install Vala
 because the C code is already generated.
 
+You also probably want to install Latexmk or Rubber. Latexmk is used by default
+for compiling documents.
+
 
 Simple install procedure
 ========================