Note: template_lvbitx.{cpp,hpp} need to be excluded from the
list of files that clang-format gets applied against.
host/lib/dep is also excluded from this change.
The function was directly accessing the error message cache, bypassing
locks, and thus could be faulty if being called the same time as another
UHD component would update the error string.
* Cleaned up usage of handles vs. handle pointers
* Store global string for last error thrown
* Removed uhd::device_addr_t handle, added std::vector<std::string> handle
* multi_usrp, multi_usrp_clock, and associated classes accessible through C
* Added Doxygen documentation explaining structure and API
* Simple RX and TX streaming examples
* Unit tests for different parts of C interface and C++ error conversion
