Add exec (#10)

* Add exec

* Fix linux tests

* unnecessary dependency

* Dont prefix ExecOptions with I

* Consistency nits

* Respond to feedback

* Add toolrunner explanatory quote

* Format

packages/exec/__tests__/scripts/print args cmd with spaces.cmd

@@ -0,0 +1,12 @@
+@echo off
+setlocal
+set index=0
+
+:check_arg
+set arg=%1
+if not defined arg goto :eof
+set "arg=%arg:"=<quote>%"
+echo args[%index%]: "%arg%"
+set /a index=%index%+1
+shift
+goto check_arg