Removed all unnecessary files from the Xcode project

Change-Id: I60c20e184f51906e6e2fb3880d593584aac0e2fb
Tested: on OS X
Fixed the web pages not scrolling by regenerating with doxygen.

Change-Id: Id1269f85ec2f522c8d4b0d05f84d050b42d70d60
Tested: on Android
Fixed a bug in the Java code generation that would generate the wrong identifier in some cases.
Also added a safety check for buffers growing past 2 gigabytes.

Change-Id: I2bca7159f606cf1c08c4391e88ef9b4c8363be06
Tested: With the Java sdk.
Documentation changes to clarify FlatBuffer internals.

Change-Id: I3759a07385f0d8d172ca2f88ac1759b71bee5a6a