jiawei, modify readme

Author: houjw11

.gitignore

@@ -30,3 +30,9 @@
 *.exe
 *.out
 *.app
+
+*~
+build/
+bin/
+.idea/
+cmake-build-debug/

README.md

@@ -51,11 +51,11 @@ if you don't know the door width and corridor width of the environment, set it a
 
 example: 
 ```
-./bin/example_segmentation ~/Freiburg79_scan_furnitures_trashbins.png 0.05 -1 -1 1.5
+./bin/example_segmentation ../dataset/input/Freiburg79_scan_furnitures_trashbins.png 0.05 -1 -1 1.5
 ```
 or
 ```
-./bin/example_segmentation ~/Freiburg79_scan_furnitures_trashbins.png 0.05 0.85 2.7 1.5
+./bin/example_segmentation ../dataset/input/Freiburg79_scan_furnitures_trashbins.png 0.05 0.85 2.7 1.5
 ```