Move ldap check to separate macro
Move mysql check to separate macro
Indent mysql macro
Fix whitespace and indentation of configure.ac

Also fix some quoting issues
/usr/local has been the default prefix since 1994
Some more cleanups
Show the defaults in the help strings
Move postgresql check to separate macro
Move oracle checks to separate macro
Move opendbx check to separate macro
Move CDB check to separate macro
Even more cleanups for configure.ac