Implemented new led status proposal
New blink patterns for safety switch, removed GPS lock indicator
Hotfix: Wrong capitalization on header file name
Merge branch 'master' into new_led_status
Change the way modules are built so that object paths are relative and use vpath for locating sources (so source paths are also shorter).

Add some basic documentation for the build system files while we're at it.
Oops, left in some test code.
Tested with PX4FMU and PX4IO with GPS and arming
Fix ROMFS dependency scan, add a warning if ROMFS_ROOT appears to be empty.
Fixed led patterns to be up to the latest specs
Added fixed wing controller example
HOTFIX: simplify symbol names going into the ROMFS object, hopefully this avoids inconsistent symbol naming on Windows.
More example fixes
Merge branch 'master' of github.com:PX4/Firmware
Make it harder to run into a non-existent uORB error
Fixed compile and logic errors, behaving now
Blink pattern fixes
Hotfix: Make the param file name less then 8 characters
Merge branch 'master' of github.com:PX4/Firmware
Merge pull request #269 from PX4/new_led_status

New led status
Hotfix: Off-by-one fix in overflow check