Flags for executing a child with its stdin and/or stdout piped back.

Enumerator:

ECORE_EXE_NONE	No exe flags at all
ECORE_EXE_PIPE_READ	Exe Pipe Read mask
ECORE_EXE_PIPE_WRITE	Exe Pipe Write mask
ECORE_EXE_PIPE_ERROR	Exe Pipe error mask
ECORE_EXE_PIPE_READ_LINE_BUFFERED	Reads are buffered until a newline and split 1 line per Ecore_Exe_Event_Data_Line
ECORE_EXE_PIPE_ERROR_LINE_BUFFERED	Errors are buffered until a newline and split 1 line per Ecore_Exe_Event_Data_Line
ECORE_EXE_PIPE_AUTO	stdout and stderr are buffered automatically
ECORE_EXE_RESPAWN	FIXME: Exe is restarted if it dies
ECORE_EXE_USE_SH	Use /bin/sh to run the command.
ECORE_EXE_NOT_LEADER	Do not use setsid() to set the executed process as its own session leader
ECORE_EXE_TERM_WITH_PARENT	Makes child receive SIGTERM when parent dies.
ECORE_EXE_ISOLATE_IO	Try and isolate stdin/out and err of the process so it isn't shared with the parent.