Added M500, M501, M503 to save certain values to a config-override file that gets loaded at boot time if present
Currently M206, M92, M301 are saved when M500 is used, M503 just displays current overriden settings
added an append to file streamthat appends and printfs to a file
Fix homing for corexy to honor the home to min or home to max setting.
swap corexy homing back to x y z
swap corexy homing back to x y z
Merge pull request #289 from wolfmanjm/upstreamedge

Add M500, M501, M503 to save certain settings
Merge remote-tracking branch 'upstream/edge' into working
Add comment to M503 indicating if override file present or not
increase precision on saved steps/mm to 5 dp
Add comment to M503 indicating if override file present or not
increase precision on saved steps/mm to 5 dp
Merge pull request #290 from wolfmanjm/upstreamedge

Add comment to M503 indicating if override file present or not
Merge remote-tracking branch 'upstream/edge' into working
refctor some code, dd comments
make dtor virtual to avoid errors

Conflicts:

	src/libs/StreamOutput.h
Make X and Y home at the same time on corexy/hbot like regular homing
Make X and Y home at the same time on corexy/hbot like regular homing

Conflicts:

	src/modules/tools/endstops/Endstops.cpp
make corexy home x and y at the same time
fix conflict
Merge pull request #291 from wolfmanjm/upstreamedge

Upstreamedge
Merge remote-tracking branch 'upstream/edge' into working
Use FileStream intead of append file stream for M500, seems to fix crash
don't use use string in appendfilestream
don't inherit from mbed:stream anymore