perf tools: Move term functions out of util.c

perf tools: Move term functions out of util.c

The term functions are needed by help.c which is going to be moved into
a separate library.  Move them out of util.c and into their own file.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/9a39c854dd156b55ebda57e427594c9a59dcb40f.1449548395.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>