added .gitignore

.gitignore

@@ -0,0 +1,15 @@
+# Lines starting with '#' are considered comments.
+# Ignore any file named paper_occ.pdf
+#paper_occ.pdf
+# Ignore (generated) html files,
+#*.html
+#Ignore tex-specific files
+#
+#Think about whether or not to include the resulting moc files
+#*.moc
+# Definitely do not look for temporary files
+*~
+# except foo.html which is maintained by hand.
+#!foo.html
+# Ignore objects and archives.
+#*.[oa]