Implement URI::addQuery

Conflicts:
	lunchbox/uri.cpp
Improve PersistentMap API

Conflicts:
	lunchbox/persistentMap.cpp
	lunchbox/uri.h
URI improvements and bugfixes

Conflicts:
	tests/uri.cpp
PersistentMap improvements and bugfixes
Be more gracious with file URIs
Fix Travis
Improve unit test
Merge pull request #123 from eile/master

URI & PersistentMap improvements