added minId, maxId to LogFileReader.traverse
modified LogStorage.searchTablet() interface
added forWrite flag to LogFileReader.traverse
changed forWrite parameter to doParallel
fixed limit, offset mismatch with result
fixed duplicated log in traverse result
fixed araqne/logpresso.com#156
Merge branch 'master' into remove-online-index-buffer

changed version to 2.1.1
Conflicts:
	araqne-logdb/pom.xml
	araqne-logstorage/pom.xml
Merge branch 'remove-online-index-buffer'