Use logging gem for all logs

Logging gem provides advanced logging features. From now on we use it
for every log call in katello. It also replaced KatelloLogger. We have
simple loggers hierarchy, they are all children of default root logger.
Only the root logger has appender that logs to just one file.

In order to make tire logging to Katello-wide logger a TireBridge was
created. It injects logging target to Tire objects. Only drawback is
that Tire does not specify log level of a message so we mark it the same
level as is set in current configuration of Tire logger.
New logging configuration

Cleanup of old configuration values. A new logging system is now
configurable via katello.yml. You can set severity for each logger,
pattern different for each environment and much more.

Also there is now fallback if anyone makes a mistake and set wrong
appender name, it will log at least to STDOUT which makes debugging less
painfull.
Syslog support

You can configure logging to use syslog instead of rolling file. You can
use type option for this purpose. Nothing extra is needed but note that
syslog has it's own severity filtering.

Syslog facility daemon is being used. Ident is set to katello (or
delayed_katello for delayed job)
Support for log trace

You can set log trace feature in logging configuratio now which will add
an extra line to every log message that displays from which file:line
and method was this message logged.

This also implies all loggers must be named in configuration. When you
add a new logger somewhere in code you must mention it in configuration
otherwise log trace feature won't work for this logger.
Remove logrotate configuration not needed anymore

Logging gem has support for log rotation by itself. We don't need
external logrotate for production and delayed job logs. Also elastic
search is now part of production log. Other logs out of katello
scope (thin server) must be still rotated by logrotate.

Katello client rotates log by itself when it reaches 1MB. It keeps 5
last log files.
Support for custom log file path
Inline console logging support

You can turn on logging directly into rails console. Also logger path is
created only when explicitely specified.
Test coverage for logging

Added rspec tests for logging. In order to test some methods I added
changed respond_to method of Katello::Config so it reflects its
redefined method_missing.
add missing log_trace option in common.logging
use same format for stdout appender as for development.log
Multiline log messages indentation

When a log message contains more than one line we indent all following
lines and add a prefix to easily see what lines are connected to which
messages.
Configuration cleanup

Configuration moved to common settings. Also candlepin loggers renamed
to cp so their names are not so long. Ignore log/*.age files that
logging creates.
Move logging configuration to defaults

Set defaults for logging so config template is clean again.
Logging configuration validation

Added validation for required logging configuration. Also moved default
path logic to configurtion lib to stay consistent.
Fix specs with new logging gem
Changed default settings

Rotate by weeks in production by default. Also don't align logger names.
do not align logger names
pull out configuration post_process down same as validation definition
add YARD log support
simplify #configure_children_loggers method