Option to set statusbar icon colors and data activity colors
- implemented StatusbarIconManager that takes care of changing icons and
applying color filters on the fly; contains caching capability
- signal icons for wifi and mobile are replaced on the fly with 
"color filter-friendly" ones coming from AOSPA
- mobile signal is colored only in case it's set to base blue in SIM
management settings - this means other 3 colors from 
SIM management settings can be used as an alternative to override
current color setting.