slightly modified / more flexible handling of --disable-debug / --enable-debug=no:
slightly modified / more flexible handling of --disable-debug / --enable-debug=no:

With --disable-debug / --enable-debug=no,
we now remove "-g" switches from CFLAGS,
but keep all other default flags (e.g., -O2 with gcc).

(
With --enable-debug / --enable-debug=yes,
we remove "-O?" switches from CFLAGS,
but keep the default "-g" switch.

With --enable-debug=auto,
we leave the CFLAGS "unharmed",
usually as "-g -O2" for gcc and "-g" for other compilers.
)

[
A potential back-port of this checkin
to the latest release branch
will only be considered after discussion
with (at least) Sjoerd and Niels.
]

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb