[LyX/master] Remove variable properly now

[Jean-Marc Lasgouttes]

commit a0fd54b2e76be640baca28da1780ad6b9a79916f
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Thu Mar 5 12:48:01 2015 +0100

    Remove variable properly now
    
    This is a follow-up to db1979f39871.

diff --git a/src/LyX.cpp b/src/LyX.cpp
index 251fe2d..0cd6e97 100644
--- a/src/LyX.cpp
+++ b/src/LyX.cpp
@@ -175,8 +175,6 @@ struct LyX::Impl {
        ///
        Movers system_movers_;
 
-       /// has this user started lyx for the first time?
-//     bool first_start;
        /// the parsed command line batch command if any
        vector<string> batch_commands;