Improved docs and formatting for RemoteBlockInStream and TachyonFile
return false after exsits check failed
Merge pull request #560 from luogankun/luogankun05

return false after exists check failed
Update doc for new CLI commands
Merge pull request #562 from Huawei-Tachyon/jira74a

Update doc for new CLI commands
Merge pull request #558 from manugoyal/remote-read-docs

Improved docs and formatting for RemoteBlockInStream and TachyonFile
format