initial code cleanup, switch to gtk3
improved makefile, readme. small code cleanups
fixed crash
fixed timer from not running
hours:minutes:seconds display implemented
added about button, interface is ready for tree to save laps
implemented laps
UI improvements
no more negative laps, bug found
added markup to timer_display: big, fat timer!
expander is centralized now
various ui changes, looks better now
added reset option
ui improvements, buttons instead of spacebar
removed unneeded headers. found bug
lap count bug fixed
lots of improvements
added license
started implementing tabs and countdown timer
removed timer