Fixed env bug seen when running init scripts as root.
Updated *_base scripts and *_init script templates to a new
1. Init scripts that use corresponding *_base scripts are
minimized so that do nothing more than set SDP_INSTANCE and
then call the corresponding *_base script.
2. The 'su' commands always pass $* instead of $1, deferring
all processing to the *_base script.
3. The shell environment is now guaranteeds to have the same
results regardless of whether it is called as 'root' or as
the defined OSUSER.
4. The p4_vars file is always sourced exactly once. Two
calls to 'source p4_vars' appear in some cases, one
immediatley before the su/exec call, and another after the
after the 'su/exec'. Only one or the other is sourced.
5. All init scripts have a reasonably consistent usage message.
6. All init scripts accept a 'status' argument.
This change fixes a bug where 'p4broker_N_init status' run as the
'perforce' user would report many pids unrelated to Perforce
if run as root, e.g. doing 'service p4broker_N_init status'.
This also eliminates a potential issue where the 'perforce'
user might source a p4_vars with a default instance in ~/.profile
or ~/.bashrc, thus invalidating the instance specified when the
user ran the init script as root.