add .gitignore for qt
implement gui base
add empty WorldWiget class
link light seek library
add setter for World/Robot model
add World#getObstacleList()
add World#getDimension()
implement WorldWidget paint event for field

- WorldWidget#paintField()
- WorldWidget#paintObjects()
implement WorldWidget paint event for robot
set color with "oddend"

https://kuler.adobe.com/oddend-color-theme-2181/
attach environment to MainWindow
add toolbar & link environment function
attach agent to MainWindow
implement redraw process

- link toolbar button to drawing process
- redraw 20fps after start button pushed
- stop redrawing after init/stop button pushed
set agent & environment to MainWindow
Merge pull request #16 from cad-san/implement-gui-sample

Make Sample with GUI(Qt)