This reverts the revert commit bc67fc97c39628c76a4dbca411b0e8a9bfaf726a,
except for the changes in BaseConfigLoader.cpp, which caused the bug
that made us revert 72cf2bdb87f09deff22e1085de3290126aa4ad05. PR 12917
contains an improved change to BaseConfigLoader.cpp, which can be merged
(or rejected) independently.

A few changes have also been made based on review comments.

Most of these changes are to improve consistency in capitalization.

This reverts commit 72cf2bdb87f09deff22e1085de3290126aa4ad05.

SYSCONF settings are getting cleared when they shouldn't be. Let's
revert the change until I get proper time to figure out why it's broken.

Some pieces of code are calling IsRunning because there's some
particular action that only makes sense when emulation is running, for
instance showing the state of the emulated CPU. IsRunning is appropriate
to use for this. Then there are pieces of code that are calling
IsRunning because there's some particular thing they must avoid doing
e.g. when the CPU thread is running or IOS is running. IsRunning isn't
quite appropriate for this. Such code should also be checking for the
states Starting and Stopping. Keep in mind that:

* When the state is Starting, the state can asynchronously change to
  Running at any time.
* When we try to stop the core, the state gets set to Stopping before we
  take any action to actually stop things.

This commit adds a new method Core::IsUninitialized, and changes all
callers of IsRunning and GetState that look to me like they should be
changed.

DolphinQt: Rework dirty flag handling in AssemblerWidget::TabTextForEditor

Putting the handling of the dirty flag in only one string makes it
clearer for translators what's going on.

This reverts the parts of commit c8c9928eb1 that made translatability
worse rather than better. Changing "Error in column %2" to "%1 in column
%2" not only means that the translators have to check the i18n comments
to know what word hides behind %1, but there's also the problem that
the translator might need to translate "Error" in this context
differently from the standalone string "Error". Having to copy-paste
some HTML tags may be annoying for translators, but it's a far less
serious problem.

Also, don't show error line numbers in the instruction patch dialog. The
input text field only accepts one line anyway.