Add LogEntryRepository and its test.
Add log-type option and list-log-types option.
Add test case to verify --log-type option specified.
refactoring around main() function.
Fix a bug "from,to" parameter converting.
Refactor tigrep::Application::run() method.
refactoring around main() function.
Merge branch 'spike-log-type-refactor' of github.com:tri-star/tigrep into spike-log-type-refactor
Merge pull request #3 from tri-star/spike-log-type-refactor

refactoring around main() function.
Add --log-type option and --list-log-types option.
Merge branch 'feature-log-type-support' of github.com:tri-star/tigrep into feature-log-type-support
list-log-types option.

Refactor tigrep::Application::run() method.

Conflicts:
	src/application.h
Merge pull request #4 from tri-star/feature-log-type-support

Add --log-type option and --list-log-types option.