merged from repo
small changes
implement CellBuffer.cell, which gives a cell for x,y. this is used several times
use Style.setAttrs in Style.Normal
sanitize style attribute setters
rename events and Screen.Fini -> Screen.Close
use t.Sync when SIGWINCH arrives
write a gotoXY method to set the cursor; throw away ununsed event code
rework acs map creation, move tscreen attributes so the reader knows which one are guarded by the mutex
sanitize key name/code preparation in tscreen constructor
rename sim_test.go to simscreen_test.go, see last commit
rename simulation.go to simscreen.go, as it contains the struct with that name
merge attr.go into styles.go, as they are closely related
rename cell.go to cellbuffer.go, this is more fitting edited online with Bitbucket
remove SimulationScreen interface
finally got rid of convey
remove convey from runes_test.go
remove convey dependency from sim_test.go
view.Cellbuffer: put code for testing if x,y is inside the view into a method