Update Build environment and include Flags for PIE support
Update minSDKversion.
See https://code.google.com/p/android-developer-preview/issues/detail?id=888 for details
Add CFLAGS for PIE to webserver
Not needed there since mongoose is static
Adding back x86 mips
Merge pull request #581 from 0-kaladin/update_build

Update build environment, add PIE, fixes issue #572, #580