Steelhead: lightsctl overhaul + helper binary

lightsctl (AKA avrlights) has been in need of an overhaul for some time.

Summary:

* Can update any continuous range of LEDs in a single call
    -existing version in CM has a buffer overflow on the stack
        (see :30 and :67-69; 8 ints are provided to store up to 32)
    -existing version in CM has a buffer overflow on the heap
        (see :74, :83-91, and :94-97; I don't know how this worked)
    -existing version in CM updates ALL LEDs each call
        (see :93; underlying system obviously supports ranged updates)

* Can set each LED's color with a single call
    -this functionality already exists, but has been refined

* Can update LEDs using octal, decimal, hexidecimal and combos thereof
    -existing version in CM only accepts decimal

* Mute LED represented independently as LED 0 for convenience
    -it's as easy as avrlights 0 1 0x886600

* Argument validation through strtol and sanity checks
    -abject failures are met with usage messages for assistance

* Well-commented with a usage message that can be displayed for help
    -existing version in CM provides no sort of guidance

* Thorough error checking
    -basically check for successful completion of every syscall

* Added in a helpful program to convert HSV to RGB
    -this is useful when attempting to display certain color patterns
    or other visual effects, such as rainbows and brightness dimming
    -allows representation of HSV without any need for float support
        (*cough* BASH *cough*)

Change-Id: I95ae98021e3998042fd738b8a1468fe44b292ad6
Add steelhead healthd

Change-Id: Ie6c4a4c695d2f2f03be3541948146610bbc001ec