adding gitignore file to repository

git-svn-id: https://dng.biozentrum.unibas.ch/svn/openstructure/trunk@2042 5a81b35b-ba03-0410-adc8-b2c5c5119f08

.gitignore

+CMakeFiles
+cmake_install.cmake
+stage
+dng
+gipltng
+ost
+*_tests
+Makefile
+CTestTestfile.cmake
+*.cxx
+.*
+!.gitignore
+CMakeCache.txt
+config.hh
+*.pyc
+index.txt
+examples_index.txt
+html
+scratch
+pov_*test.pov
+pov_*test.inc
\ No newline at end of file