Added a link to the webui to show the Meta Server Configuration
Meta server: change default for apppend placement to turn off master/slave taking into the account master / slave assignment in order to make write append work with default configuration with arbitrary replication. Add the configuration parameter description to meta server configuration file.
Chunk server: fix default setting with chunk server hello with authentication off, in order not to send file ids to the meta server. To enable chunk servers to make compatible with older meta server chunk server property chunkServer.meta.noFids = 1 cam be set in the chunk
server configuration file.
Merge pull request #45 from echenj/show_meta_conf

Added a link to the webui to show the Meta Server Configuration
Meta server: implement configuration values filtering with ping response. Space delimited list of configuration key prefixes to omit from ping response can be specified by setting metaServer.pingDoNotShow parameter. The parameter's default is "metaServer.clientAuthentication. metaServer.CSAuthentication.".
Meta server: return EAGAIN in the case when chunk access tokens are required with read lease, but no valid chunk server keys exists yet, in order to make the client retry later when the chunk server key(s) will be updated.
Web ui: use json formatter, if available, to create configuration json response. Use "sortable" html table to display configuration in the web ui.
Web ui: html escape configuration key / value pairs.
Qfs tool: implement "-lst" command to list summary for the specified tier range.
Tools: qfs tool add client parameters description to help message.
Meta server: remove incorrect lease time conditional prefix with single chunk read lease acquisition, always return chunk server and chunk access tokens with authentication enabled regardless of the lease time value, in order to allow client to access chunk server without creating read lease in the case where the client needs to obtain the last chunk size in order to determine logical file size. Add chunk access count to read lease RPC show method in order to facilitate debugging.
Client library: implement retries with get layout returning "again" for the last chunk due to no replicas available in the logical file size computation logic. This is needed to correctly handle file open for non striped files, where, in typically rare cases, the chunk servers can disconnect before the chunk replicas become stable.
Examples: sample servers setup: remove create empty file system flag from configuration, as this should rarely be used, if ever, and sets a bad / misleading example, even now when chunk files are "protected" by file system id.
Chunk server: eliminate lint warning.
Tools: qfs tool implement fs.columnSeparator configuration parameter. The parameter can be used to set -ls[rst]* and -count column delimiter (single character). C escape sequences can be used to specify character code.
Chunk server: chunk directory info RPC: add non stable chunk count, space used, space not stable, fix available chunk header.
Chunk server: fix rare failure uncovered by the endurance test with failure simulation when the unstable chunk is discarded due to version change coming at the moment when writes are still in flight. Most likely I forgot to remove this condition when I re-implemented (a few years ago) version change to handle this case by executing chunk header header write and rename after write completion. For now add parameter to turn this condition off by default, by allowing version version change with writes in flight in order to prevent erroneously discarding unstable chunk on re-connect.
Chunk server: eliminate possible compiler warning due to integer to boolean assignment.
Client library: retry chunk lease acquisition in the file size calculation path when no chunk replicas available.
Client library: retry get layout in logical file size calculation path with no chunk replica available, when meta server returns "host not reachable" status.