Remove online mbed SDK release.

Preparing for switch to mbed SDK being built from sources in gcc4mbed.
mbedSDK version 20130809-0843613136dc30cba6f731e9b6f273e4942256c2

Initial mbed github commit is for this version of the sources:
  https://github.com/mbedmicro/mbed/commit/0843613136dc30cba6f731e9b6f273e4942256c2
Modify mbed lib sources to silence GCC warnings.
Updates to .gitignore

Just ignore output file extensions like *.o, *.a, etc instead of
the output directories.  I also removed some old file types that
no longer get generated within the gcc4mbed directories such as
.svn, .hg, etc.
Update makefiles to build mbed SDK sources.

This initial commit with support for building the mbed SDK sources as
part of the project build process, just works for LPC176X targets at
this time.  Future commits will add support for a few other targets.

When you build a sample like HelloWorld, it has a dependency on
libmbed.  The makefile used to build HelloWorld ends up including
build/arm-common.mk which has rules for building the mbed SDK and
can therefore build the mbed SDK library if it doesn't already exist or
its sources have been updated.

I introduced a new rule: clean-all.  The old clean rule will just clean
the sample output binaries.  clean-all does this and instructs make to
clean out the mbed SDK binaries as well.  While it is necessary to
conduct a "make clean" when you switch between sample build types, it
should be rare that you ever need to clean-all the mbed SDK binaries.
That's why the rules are separate.
Rename makefiles

Perform a makefile rename in preparation for adding support to build
LPC11UXX binaries as well.
Initial support for multiple devices.

I have plumbed in the basics of allowing a project to be targetted to
multiple platforms.  For now it accepts the LPC1768 and LPC11U24
targets.

NOTE: I have more work to do before the LPC11U24 target is actually
      functional.
Get LPC11U24 builds to work.

Can now build and run the following samples successfully for both
LPC1768 and LPC11U24:
  HelloWorld, Ticker, StdIO, LocalFileSystem, FileTest
Fix GCC warnings in mbed SDK LPC11U24 HAL code.
Correct GCC warnings in KL25Z mbed HAL code.
Add support for the KL25Z device.

The HelloWorld, Ticker, and StdIO samples can be built for this device.
The device doesn't have built-in local storage so that LocalFileSystem
and FileTest samples aren't built for it.
Merge in latest from mbed's github repo
Update LPC1768.ld linker script to work with net stack.

The original script assigned memory ranges to USB_RAM and ETH_RAM but
it never placed any section data in those regions.  I added clauses
towards the bottom of the script to place data that the programmer
has marked for the AHBSRAM0 and AHBSRAM1 sections into these regions
of RAM.  Previously the data destined for these sections was being
placed in the lower 32K RAM bank and overflowing it at link time.

I also added a few Image$$ linker symbols to mimic those used by the
online compiler.  I have had samples in the past which took advantage
of these to display static memory statistics for each SRAM region.

I also changed LENGTH=0x7F38 to LENGTH=(32K - 0xC8) to make it more
consistent with the sizing of the other regions in this script which
use human readable K sizing information.  The 0xC8 subtraction reflects
the starting offset of 0xC8 for this region.
Fix GCC warnings in mbed netstack code.
Add support for rtos and network stack

It is now possible to use the rtos and networking components from the
mbed github repo to build your projects.  The TCPSocket_HelloWorld
sample is an example of how this is used.
Refactor makefiles to reduce rendundant code.

All of the device specific makefiles were setting up the MBED_INCLUDES
variable the same and pulling in the same mbed component makefiles.
Updating mbed sources to latest github commit.

Updated to:
    https://github.com/mbedmicro/mbed/commit/de715aed95162eb2e4a82867e57abcf545b2902c
Pulling in latest from mbedmicro/mbed

https://github.com/mbedmicro/mbed/commit/ff55aa3e130952a9b8db9693cb42be5f72ba3efb
Update to latest mbedmicro/mbed commit

https://github.com/mbedmicro/mbed/commit/2433eebf244ead7eed6d50a4965a6cd03304de4c
Update to latest mbedmicro/mbed commit

https://github.com/mbedmicro/mbed/commit/4d26e2ef4abf130fda3fb78a4de17736661dc8e8