Started experimental "session" branch.

Using code from @spmallette
(https://github.com/tinkerpop/rexster/tree/master/rexster-protocol/src/m
ain/java/com/tinkerpop/rexster/client) as a starting point.
Rename src/main/java/com/fabric/rexconnect/CommandHandler.java to src/main/java/com/fabric/rexconnect/core/CommandHandler.java
Rename src/main/java/com/fabric/rexconnect/GremlinExecutor.java to src/main/java/com/fabric/rexconnect/core/GremlinExecutor.java
Rename src/main/java/com/fabric/rexconnect/HeartbeatMonitor.java to src/main/java/com/fabric/rexconnect/core/HeartbeatMonitor.java
Rename src/main/java/com/fabric/rexconnect/RexConnectConsole.java to src/main/java/com/fabric/rexconnect/main/RexConnectConsole.java
Rename src/main/java/com/fabric/rexconnect/RexConnectServer.java to src/main/java/com/fabric/rexconnect/main/RexConnectServer.java
Attempted session-based RexPro.
Attempting another RexPro session approach.
Continued progress on session-based RexPro.
Completed initial session-based RexPro client.
Added session controls to the console.
Implemented initial command/arg infrastructure.
Added initial TCP request/response classes.
Completed initial Console functionality.
Added 'config' command support.
Added JSON formatter; my OCD couldn't handle the default.
Updated scripts. Removed JLine usage.
Improved output for "C" syntax highlighting (Fixes #5).
Refactored pretty printing. Implemented new Server mode.
Updated command response "results" type.