Change naming and formatting convention, fix line endings, fix warnings

[cschreib]

This does the following:

• Setup clang-format with new formatting convention
• Change the entire code base to not use hungarian notation (yay)
• Disable warnings selectively in third-party headers, and re-enable these warnings in the rest of the code base
• Move periodic_timer in its own header/cpp
• Make gradient a simple struct
• Remove the strata pointer in level
• Rename blink_speed to blink_period in edit_box
• Fix a few bugs found along the way