Update version check to work with >= 4.3

Now that 4.4 is out, the check was failing and not properly setting up
the su daemon.

Using POSIX sh parameter substitution allows us to extract the major and
minor version numbers from ro.build.version.release in build.prop and
compare them.

This was tested on a Nexus 4 running 4.4.
Merge pull request #194 from tmzullinger/kitkat-version-check

Update version check to work with >= 4.3
README: Update build information

Specify the required SDK API and NDK versions.  Add info on signing the
release build, as build.xml is hardcoded to use Superuser-release.apk only.
reboot: Build utility from source

This was based on disassembling the HTC ARM reboot binary currently
shipped with Superuser.  It attempts to mimic the behavior of the
original program.

Future work may involve cleaning it up, removing the HTC-specific
features, etc.
MainActivity: Split getArch() into a common function
Use new assets/<ARCH>/reboot binary

Now that we are building the reboot binary from source, we'll need to
retrieve it from the proper subdirectory according to the device's CPU
architecture.
Add MIPS support

Tested on:
 - Ainol Novo 7 Paladin (JZ4770 MIPS SoC) with ICS 4.0.3 and CWM
 - Nexus 5 (ARM) with KK 4.4 and TWRP

Not tested on x86.

I checked to make sure "uname -m" is standard in busybox (not a feature
flag).  "uname" doesn't seem to exist at all in AOSP, so without busybox,
the original script probably wouldn't have detected the architecture
correctly.
Merge pull request #195 from cernekee/mips-v1

Add MIPS CPU support
Merge remote-tracking branch 'koush/master' into cm-10.2
comment out hte multiuser stuff that is breaking regular ndk builds

Change-Id: I535472084833883e5bedb1631dcb309b6d9e77a3
1022

Change-Id: I36b8e616895ccaeaa1d886346ba18e27cef3c63a
execv invocation fixes

Change-Id: I80e7100a834b7eca2d9c8560c221cffd41492f03
README: Update required SDK and NDK versions
update-binary: Fix 4.3+ version check

In Bug #194 a check for 4.3+ was added, but checking major and minor
separately would yield an incorrect result on e.g. v5.0.  Fix this.
require that --daemon is uid/gid 0
execv invocation fixes

Change-Id: I80e7100a834b7eca2d9c8560c221cffd41492f03
Fix superuser when using ART.

Change-Id: I8ef488afe6f7912d8fac205088c3b431a5cb4a35
Merge pull request #198 from cernekee/version-v1

Trivial fix for v4.3+ version check logic
Revert back to original daemon client usage behavior.
Fix ART by always using the daemon client on API 19+.

Change-Id: I69b31e339cec2f71d2de9b0468d7dcab1d3ea078
Superuser: CA translations 

Change-Id: I2ce0e0766ce56a506364d9b5a982fb86006ce205
Merge "Revert back to original daemon client usage behavior. Fix ART by always using the daemon client on API 19+." into cm-10.2