XD-643 Adding mapping for column names with underscore

We need to add support for matching column names with underscores like "user_name" and map them to camel case style keys like "userName" in the JdbcMessagePayloadTransformer to insert table data using the JDBC sink
XD-643 - convert spaces to tabs
XD-653 - Add ALLOW_SINGLE_QUOTES to json mappers
XD-632: Add --file & --contentType support to http post command
* Add support for file to http post + enhance http source to honor Content-Type if present
* Use ISO-8859-1 as the default charset
XD-648 Regression test on file source

fix dir attribute of file source

rename duplicate parameter

add basic tests against file source/sink

remove fromEnd
XD-655 - Trimmed http post command output
XD-650 Ensure a clean build after running gradle->refresh
XD-660 - Renamed XD shell scripts to xd-shell
XD-635: Updated all polling sources to use fixed-delay and fixedDelay property
Fix typo at twittersearch module's fixedDelay property for inbound-channel-adapter poller
XD-663 Changing to runtime FS_DEFAULT_NAME_KEY constant

Need to use reflection to access the value for the specific Hadoop version used

This avoids Hadoop warning messages in Hadoop 2.0 based distros
XD-666 Fix Conversion on Taps

The channel registries did not apply conversion logic to taps.

This meant that, for the Redis transport, the internal transport
headers were included in the tapped data and, for Rabbit, the
content type was incorrect.

Apply the same logic to taps that is applied to inbound.
XD-544 - Fix In-Memory Analytics

on merge: added not-null assertion
XD-547 Add AggregateCounter display
- Added AggregateCounter display command with from, to, (XD-665)lastHours, lastDays, resolution and pattern options
- Fixed missing aggregatecounter value into counts array for the given interval
 - the end time interval 'value' was not added into the counts array as the size
   calculated was missing the end time interval.
  - Fixed DeepAggregateCountResourceAssembler, RedisAggregateCounterRepository & InMemoryAggregateCounter
- Added joda-time dependency to spring-xd-rest-client project
 - Handle from/to joda time query-params in AggregateCounterTemplate

XD-547 Fix AggregateCounterTests to include the end time's metric
Remove unwanted throws clause from AggregateCounterOperation's retrieve method.