base: do not allow unnamed threads

fix #901
gems: provide file to terminal service

Fixes #911.
hw: differ ID allocators even with same size

Previously, if two ID allocators for different kernel objects had the
same size, the kernel-object framework managed both objects types
through the same allocator instance. This is caused by the use of
unsynchronized singletons in the accessor functions and can be avoided
by creating new types through inheritance instead of using typedefs.
Anyways, this fix is a little bit ugly and should replaced by avoiding
the use of unsynchronized singletons in the future.

fix #906
Make NIC RX/TX buffer sizes configureable in libc

* Remove far too low default values from Nic::Connection constructor
* Extend lwip initialization function with desired TX/RX buffer sizes
* Add configuration possibility to libc_lwip_dhcp plugin to define
  buffer sizes, like the following:

  '<libc tx_buf_size="1M" tx_buf_size="1M"/>'

Fixes #892
noux: use lwip dhcp plugin, avoid code duplication

Ref #892
i.MX53 tablet: handle >1 button events concurrently

By now, only one button press/release event per IRQ was handled correctly.
Pressing and/or releasing several buttons concurrently could bring the input
driver into an inconsistent state.

Fixes #913
i.MX53 tablet: complete IOMUX routes for display

For the framebuffer driver of the i.MX53 platform to work even when u-boot
didn't prepared the display previously, there were some IOMUX routes missing.

Fixes #914
i.MX53: add config lib to GPIO driver (fix #915)
i.MX53: fit into u-boot's memory layout on tablet

Fixes #917
base/os: catch Ipc_error messages in Service class

Fixes #910
platform_drv & exynos5: provide HDMI switches

ref #796
framebuffer: support HDMI@1920x1080p on exynos5

ref #796
fb test: support exynos5

ref #796
fb test: view multiple pictures

ref #796
arndale: specs to enable demo scenario

ref #796
fb & exynos5: avoid USB HID problems with FOC

USB HID gets stuck due to strange kernel error
as HDMI starts simulatnously. This workaround
delays HDMI init by a second (only in case we
build for Exynos5 & FOC with USB) to let
scenarious like demo get their USB HID started
without much CPU load.

ref #796
demo: support exynos5

fix #796
cli_monitor: Init Ram::_resource_avail_sigh

Thanks to Stefan Kalkowski for the report.
Ring_buffer: add 'avail_capacity()' function

The 'avail_capacity()' function returns how many more elements would
currently fit into the ring buffer.

Fixes #921.
Ring_buffer: make synchronization optional

With this patch, the 'Ring_buffer' class can be made unsynchronized by
setting the 'Ring_buffer_unsynchronized' policy as third template
argument.

Fixes #922.