ROCm release v1.1.0

cleaning up README, moving some of the info to the wiki

Merge pull request ROCm#16 from RadeonOpenCompute/master

update installation path, adding debian package dependencies

[lib] remove __cxa_thread_atexit to support CentOS

glibc on CentOS doesn't have facility to support destructing C++11 thread_local
objects.  Remove related codes from HCC runtime library to support CentOS.

For now, HCC applications shall refrain from creating C++11 thread_local objects
 especially on CentOS.