Profile: rename to ProfileLoader

* Avoid misunderstood with users: a profile is a map<string, string>,
and a ProfileLoader manages a list of profiles.
* Rename typedef:
     * ProfileDesc to Profile.
     * ProfilesDesc to Profiles.
Merge pull request #125 from cchampet/dev_rename_Profile_to_ProfileLoader

Profile: rename to ProfileLoader
Merge branch 'master' of https://github.com/avTranscoder/avTranscoder into dev_setFrame

Conflicts:
	src/AvTranscoder/transcoder/StreamTranscoder.hpp
	src/AvTranscoder/transcoder/Transcoder.cpp
	src/AvTranscoder/transcoder/Transcoder.hpp