All test scripts to be executed are now named as T\d\d\d-name.sh,
numers in increments of 10.
This eases adding new tests and developers to see which are test scripts
that are executed by test suite and in which order.
Use realpath to canonicalize the config path before writing.
Previously 'notmuch setup' and 'notmuch config set' overwrote the
config file even if it was a symbolic link.
There are currently 45 TESTS scripts. 36 of those load
test-lib.sh using '. ./test-lib.sh' and 9 '. test-lib.sh'.
In latter case test-lib.sh is first searched from directories
in PATH (posix) and then from current directory (bash feature).
Changed the 9 files to execute '. ./test-lib.sh'. The test-lib.sh
should never be loaded from directory in PATH.
Add a command to list all configuration items with their associated
values.
One use is as follows: a MUA may prefer to store data in a central
notmuch configuration file so that the data is accessible across
different machines, e.g. an addressbook. The list command helps
to implement features such as tab completion on the keys.
