pgsql: libpq: Trace all messages received from the server

libpq: Trace all messages received from the server

Not all messages that libpq received from the server would be sent
through our message tracing logic. This commit tries to fix that by
introducing a new function pqParseDone which make it harder to forget
about doing so.

The messages that we now newly send through our tracing logic are:

- CopyData (received by COPY TO STDOUT)
- Authentication requests
- NegotiateProtocolVersion
- Some ErrorResponse messages during connection startup
- ReadyForQuery when received after a FunctionCall message

Author: Jelte Fennema-Nio <postgres(at)jeltef(dot)nl>
Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b8b3f861fbd7ff40055225ec48cec97df925ff04

Modified Files
--------------
src/interfaces/libpq/fe-auth.c | 21 ++++++++++++
src/interfaces/libpq/fe-connect.c | 12 ++++---
src/interfaces/libpq/fe-misc.c | 15 ++++++++
src/interfaces/libpq/fe-protocol3.c | 38 +++++++++------------
src/interfaces/libpq/fe-trace.c | 68 ++++++++++++++++++++++++++++++++++---
src/interfaces/libpq/libpq-int.h | 1 +
6 files changed, 124 insertions(+), 31 deletions(-)