NCSA TeraGrid SoftEnv keys

[Rick Kufrin <rkufrin@ncsa.uiuc.edu>]

There are new softenv keys available on Mercury for the following 
packages:

+mpip
+papi
+papi3
+perfmon
+perfsuite
+perfsuite-intel
+vprof

These should set up PATH, LD_LIBRARY_PATH, etc to help make it easier to
access these packages on the system.  There are also package-specific
variables set to hopefully make it easier to have a "generic" Makefile,
for example, after adding +papi3, you have:

PAPI_INCDIR=/usr/projects/perftools/papi3/include
PAPI_LIBDIR=/usr/projects/perftools/papi3/lib

I don't believe this convention is followed elsewhere at the TG sites,
but thought it might be useful.

We have both PAPI 2 and 3 available on the system in case some users have 
not yet converted, but conversion to PAPI 3 is the way to go at the 
earliest opportunity.

For mpiP use, remember to also include H-P's libunwind to get proper call 
path output.  This is available in the /usr/projects/perftools/libunwind 
area.

Thanks to hg-admin for the help in key setup.

Rick