udp: fix ENOBUFS with send/retry for udp socket
uhd: changed version number to 3.4.5
Merge branch 'maint34' into maint

Conflicts:
	host/cmake/Modules/UHDVersion.cmake
uhd: changed version number to 3.5.1
cmake: Allows Unix systems with /usr/lib64 to use Boost installations in non-standard locations
Merge branch 'maint34' into maint