[PATCH 5/8] Add new command "check-config" to initctl.

[James Hunt]

Add "check-config" command to initctl. This requires the "show-config"
feature.

* util/initctl.c:
  - New functions:
    - allow_event(): Determine if specified event is erroneous or not.
      Handles globbing.
    - allow_job(): Determine if specified job is erroneous or not.
      Handles variables (such as instance variables).
    - check_condition(): High-level function to handle checking start
      on/stop on conditions.
    - check_config_action: Handler for "check-config" command.
    - display_check_errors(): Display errors from expression tree nodes
      that are in error.
    - eval_expr_tree(): Evaluate expression tree.
    - ignored_events_setter(): handler for '--ignore-events' command-line
      option for "check-config" command.
    - tree_filter(): Used for filtering expression tree nodes.
  - show_config_action(): Update for check-config mode.
  - job_class_parse_events(): Update for check-config mode.
  - job_class_show_emits(): Update for check-config mode.
* util/initctl.h:
  - Added structs for JobCondition, CheckConfigData and ExprNode.
  - New macros: MAKE_EXPR_NODE() and MAKE_JOB_CONDITION().
* util/tests/test_initctl.c:
  - test_check_config(): New function to test "initctl check-config".
  - main(): Added call to test_check_config(), conditional on
    a non-chroot environment and a working D-Bus system.
* util/man/initctl.8: Updated for "check-config" command and associated
  options.
* Changelog: updated.
* conf/rc-sysinit.conf: Added emits stanza as required by
  "initctl check-config".

Code:

https://code.launchpad.net/~jamesodhunt/upstart/upstream-initctl-check-config

Merge Proposal:

https://code.launchpad.net/~jamesodhunt/upstart/upstream-initctl-check-config/+merge/63350


Regards,

James.