Fix for lower case filenames

Some small speedups

forced by the user

into tetra.spaceapes.com:/home/jcole/bk/mysql

extern "C" {

into tetra.spaceapes.com:/home/jcole/bk/mysql

clean up PostgreSQL section

Clean up 'unused argument' warnings

Add extern "C" { ... } in my_pthread.h

Fix bug in isamlog
Add argument types to function declarations.

Patches required by Gemini
Fix to properly detect if there is an active transaction in InnoDB
Fix to not lock thread structure when doing automatic rollback when thread ends
Allow -O lower_case_names=0 on UNIX

  Fixed danish SunSite mirror

Let myisamchk generate a new checksum for compressed data.
Don't unconditionally force filenames to lower case on windows.
Update mysqltest to match 4.0 source (to get some of the new bug fixes into 3.23)

into tetra.spaceapes.com:/home/jcole/bk/mysql

do val_int() on their arguments before starting the computation. 
Similar fixes are need for +-* and probably several other but I want
to make sure Monty is fine with my fix approach before changing a lot
of code. 

Amazingly,
this bug is not as critical as you would expect since very few functions do val_int()
on their arguments ( from_unixtime(), sec_to_time()), and those not
very frequently perform a computation on their floating point arguments.
which is probably why no one has yet reported this bug. Another 
possibility is that the result is usually wrong by no more than 5%,
which makes it hard to catch it. I found it when trying to compute mile
splits for 30:47 10K - it told me 5:07, and I knew it was wrong because
5:00 mile gives you 31:08. However, if I had not run as many 10K races,
I would have easily believed that 30:47 10K is a 5:07 mile pace and 
would not have noticed the bug.

into mysql.sashanet.com:/home/sasha/src/bk/mysql

  Fixed contributed software link