sbt/main
Eugene Yokota f3038167a5 Fork server if it's not running
Fixes https://github.com/sbt/sbt/issues/3508

This forks an instance of sbt in the background when it's not running already.

```
$ time sbt -client compile
Getting org.scala-sbt sbt 1.2.0-SNAPSHOT  (this may take some time)...
:: retrieving :: org.scala-sbt#boot-app
	confs: [default]
	79 artifacts copied, 0 already retrieved (28214kB/130ms)
[info] entering *experimental* thin client - BEEP WHIRR
[info] server was not detected. starting an instance
[info] waiting for the server...
[info] waiting for the server...
[info] server found
> compile
[success] completed
sbt -client compile  9.25s user 2.39s system 33% cpu 34.893 total
$ time sbt -client compile
[info] entering *experimental* thin client - BEEP WHIRR
> compile
[success] completed
sbt -client compile  3.55s user 1.68s system 107% cpu 4.889 total
```
2018-06-25 22:37:22 -04:00
..
src Fork server if it's not running 2018-06-25 22:37:22 -04:00
NOTICE Add, configure & enforce file headers 2017-10-05 09:03:40 +01:00