added unit tests for IndexParser
improved documentation for parser package
can now display multiple day tasks
Merge https://github.com/cs2103-t10-1j/main into HEAD

Conflicts:
	LifeOnLine/bin/parser/DateParser.class
	LifeOnLine/bin/parser/DateParserTest.class
	LifeOnLine/bin/parser/LOLParser.class
	LifeOnLine/bin/parser/LOLParserTest.class
	LifeOnLine/src/parser/LOLParserTest.java