pgsql: When trace_lwlocks is used, identify individual lwlocks by name.

When trace_lwlocks is used, identify individual lwlocks by name.

Naming the individual lwlocks seems like something that may be useful
for other types of debugging, monitoring, or instrumentation output,
but this commit just implements it for the specific case of
trace_lwlocks.

Patch by me, reviewed by Amit Kapila and Kyotaro Horiguchi

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/aa65de042f5828968f2f6cd65f45c543a40cc3e6

Modified Files
--------------
src/backend/Makefile | 14 ++++-
src/backend/storage/lmgr/.gitignore | 2 +
src/backend/storage/lmgr/Makefile | 11 +++-
src/backend/storage/lmgr/generate-lwlocknames.pl | 67 ++++++++++++++++++++++
src/backend/storage/lmgr/lwlock.c | 60 +++++++++++++------
src/backend/storage/lmgr/lwlocknames.txt | 47 +++++++++++++++
src/include/storage/.gitignore | 1 +
src/include/storage/lwlock.h | 52 +----------------
src/tools/msvc/Solution.pm | 16 ++++++
9 files changed, 201 insertions(+), 69 deletions(-)