Merge pull request #9 from ryandoherty/master

Minor UI improvement to tracks config
trying sliders
Merge branch 'master' of github.com:autosportlabs/RaceCapture_App
Improve README
replace modern menu with stock kivy bubble popup
Merge branch 'master' of github.com:autosportlabs/RaceCapture_App
changed gauge customization to bubblebutton
restored samplethread in databus
WIP for channel customization view. added min/max values and working on layout
slider ranges wip
range selection color working; need to fix layout
added color picker views
improved layout of color picker
hooked up colors; init colors upon gauge creation from user prefs
select customization view options intelligently based on type of gauge being customized. auto-dismiss popups after timeout
refined dialog auto-dismiss and switched to Clock.event
re-ordered system channels to put more interesting channels at top
require channel selection acknowledgement to prevent accidental selection and automatic dismissal
prevent multiple bubbles from popping up; show channel name in customization dialog
default ranges to channel meta min value, for ease of use