更新安裝Suggests的說明
Merge pull request #52 from wush978/master

resolve dependency issue and implement Basic_file
add data.table package into DESCRIPTION / close #57
add sqldf package into DESCRIPTION / close #59
Merge pull request #58 from c3h3/master

add data.table package into DESCRIPTION / close #57
Merge remote-tracking branch 'twruser/master'
resolve issues of DA