Improve repository browsing speed #192
- refresh repository list while browsing only if path is not found
- reduce max-depth during refresh (from 5 to 3)
- reduce number of calls IO operation
- improve caching of information to avoid multiple IO call to get the same information
- improve test coverage with parameterised tests
- clean-up librdiff (remove obsolete stuff)
Edited by Patrik Dufresne