moved disk_ecryption table spec to crossplatform
link libcryptsetup
implemented get cipher type and cipher_mode:
more idiomatic c++11
no need to explicitly call std::string constructor to convert char * to std::string
update cryptsetup sources for centos
add function prototype for older libcryptsetup which is in centos6
ifdef check for centos6 which uses older libcryptsetup
remove forward declared functions defined in libcryptsetup, stylistic changes
