fixed undo bugs, now doing an action that writes to the file will clear all redos
created instantSearch method in InputFieldViewManager
removed test comments from KeywordDetector
added getter and setter for selectIndex in Keyword Class
changed keyworddetector to a simpleton
KeywordDetector now changes selectIndex in InputFieldViewManager
removed setKeywords from getKeywords in CommandParser
removed all keyword selectindex code
added getter for taskData in TaskListViewManager
implemented instant task cell highlighting for update/delete/done/undone
implemented getTasksStartingFrom, getTasksEndingBy, getTasksWithinDateRange in TaskController
set default sorting style
Selected task cell is now highlighted in black. Close #185
getLastModifiedUUID in ModelManager
Disabling showErrorDialog for now
Merge branch 'staging' of https://github.com/cs2103aug2014-w13-1c/main into staging
implemented dividers for undone tasks (default view)
undo/redo buttons are greyed out if the stack is empty
Merge pull request #225 from cs2103aug2014-w13-1c/jin/gui

Visual improvements.
Merge branch 'staging' of https://github.com/cs2103aug2014-w13-1c/main into jolly/gui