TS-2202: remove manager error and fatal useless error message

we should log errno and strerror(errno) only when errno != 0.
the errno parameter should pass by the caller.
functions mgmt_elog and mgmt_fatal changed
TS-2302: rename LoggingMode values for improved clarity
TS-2302: add const to LogSock::is_connected
TS-2302: add TS_NONNULL compiler attribute
TS-2302: fix some spelling
TS-2302: merge Log::error into Log::va_error

These functions are supposed to be identical, but had diverged.
Merge them so that this  can't happen. Also add format checking to
Log::error().
TS-2302: remove ASCII_PIPE_FORMAT_SUPPORTED

ASCII_PIPE_FORMAT_SUPPORTED was used to only support logging to
pipes on Linux and Solaris. All the platforms we support have named
pipe support, so we should always enable this.
TS-2302: LogUtils wants to be a namespace, not a class
TS-2302: simplify log config variable registration
TS-2302: permanently enable IOCORE_LOG_COLLATION
TS-2302: add LogObject::va_log() and use it to implement TextLogObject message formatting
TS-2302: move predefined logging formats to a separate file
TS-2302: separate predefined formats from LogFormat

LogFormat now only knows about text and custom logs. LogConfig still
have some knowledge of custom formats, but it is largeley separated
and doesn't have a LogFormat dependency any more. Remove various
predefined log constants and apply addition const to pass format
strings around.
TS-2302: rename log format and file type constants for clarity
TS-2302: split LogConfig::create_predefined_objects_with_filter

Split the guts of LogConfig::create_predefined_objects_with_filter
into LogConfig::create_predefined_object so that we can later use
it to create an error log object.
TS-2302: convert Log::error_log into a generic prefedined LogObject

Initialize LogObject pointer arrays to NULL before using them. Use
const accessors to get to LogObject::m_name. Sprinkle more const
through the logging API.

Use the standard ConfigProcessor pattern to reload LogConfig. This
removes part of the need to keep a global array of inactive LogObjects.
Using newDeleter() in LogObjectManager::unmanage_api_object(),
removes the rest of this need. Now the whole Log::inactive_object
array can be removed.

Using the ConfigProcessor reload pattern also fixes a memory leak,
since previously the old LogConfig object was never freed.

Fix LogObjectManager::transfer_objects(). Previously, matching
objects would be assigned to the new manager, but also left on the
old manager, leaving it unclear who should have ownership of which
log object.

Move a bunch of inline LogObjectManager methods to the .cc file
where they are mre easily accessible. None of these are called often
enough to justify being inline.

The global Log::error_log is now managed my the log object manager
just like other predefined log objects. This lets us remove code
in a number of places that were treating is specially. It also fixes
a log collation bug in LogConfig::init(). This function attempts
to figure out which log space threshold to use. If all the logs are
being collated, then it used the orphan space value. The problem
is that the error log was never checked (and it is never collated),
so enabling log collation and making a poor choice of space thresholds
causes error logging to stop. Like the rest of the bugs here, the
fix is to stop treating the error log specially, and bring it into
the log object manager.
TS-2302: allow predefined formats to specify log collation support

Directly specify the log file format in the predefined format
structure. Specify whether this predefined log format supports log
collation or not. Currently the error log does not support collation.
TS-2302: update CHANGES