Expands ProfileManager and profile unit tests

Methods for deleting, creating, and listing
profiles. Also modifies get_profile by adding
an extra arg to specify whether a non-
existing profile should be auto-created.

Adds unit tests to test_profile.

Methods added:
- create
- list_profiles
- delete

Related to #632
Fix #654. Recording from USB Source Broken

Adds methods to generate valid default values for
plugins with multiple input sources.

Affected plugins:
- USB video source
- Firewire video source
- Pulse audio source
Fix #652 Show highest priority log message in status bar
Fix #655 Error when logging a non-string
Insert comment on new tests
Add non-functional test functions for click_add_talk, show_save_prompt, and click_talk
Remove unnecessary comments
Added some comment to test_click_add_talk.py
Add singleShot test to test_click_add_talk
Remove whitespace
Comment out glitchy test
Add SavePromptWidget.py file
Add test SavePromptWidget to talk editor
Remove unused modules
Refactor talkeditor save prompts
Clean up talkeditor.py refactor