Cleanup config reading failure error logs

This cleans up the log when sway fails to read a config file. The
following changes have been made:
- A missing error message has been added to the log when the config file
is a directory instead of a regular file
- In main, `goto` statements have been added after the `sway_terminate`
calls instead of wrapping every block in `if (!terminate_request)`
- Unnecessary NULL-checks around calls to free in `main` have been
removed
- Deferred command execution has been extracted to a separate function
and the `Running deferred commands` log message will not be shown when
there are no deferred commands.

0 files changed, 0 insertions, 0 deletions