Add the "Esri Spatially-Enabled Database" file format to the magic.txt file.
Enhance the timer in the shell to show wall-clock time in addition
to user and kernel CPU time.
Fix harmless compiler warnings.
Enable some more tests on Windows.
Update comments in the MSVC batch build tool.
Fix a problem in os_unix.c causing compilation failure if SQLITE_DEBUG and SQLITE_MAX_MMAP_SIZE=0 are both defined.