Merge pull request #32 from dozeo/feature/polarssl

PolarSSL added as submodule, fixed install scripts build dependencies for all platforms
Fixes download of yasm, the sources are now available in the download section on github.
Fixed copying the right librtmp file to the install directory

* `librtmp-0.dll` is copied to the destination directory
* the build dependencies now depend on this file instead of `librtmp.dll`
Includes a small fix in rtmpdump project
On OSX the yasm source tarball is downloaded from the github repository
Merge pull request #33 from dozeo/fix/win32_build

Fixes copying of dependencies to destination folder, yasm is downloaded from github.
Changed `wget` to `curl` for downloading yasm
Merge commit 'fc1b67d8'
Merge pull request #34 from dozeo/develop

Changed wget to curl when downloading yasm
Wget is downloaded now, it used for Windows buildserver to support download of files with https protocol.
Merge branch 'master' into fix/win32_build
Merge pull request #35 from dozeo/fix/win32_build

Wget is downloaded on Windows to support https downloads
On Windows the `unzip` command line tool is downloaded in build script.

* build script downloads the `unzip` command line tool on Windows
* on one of the Windows build machines the tool did not extract a zip file
Merge pull request #36 from dozeo/fix/win32_build

On Windows the `unzip` command line tool is downloaded in build script.
The dependency build script on OSX builds PolarSSL from submodule
Protocols `rtmpte` & `rtmpts` are activated in the dependencies scripts for all platforms.

* streaming support for protocols `rtmpte` & `rtmpts` are included in build scripts
* dependencies must be rebuild to include changes
Merge branch 'master' into feature/rtmpte
Merge pull request #37 from dozeo/feature/rtmpte

Protocol rtmpte enabled in ffmpeg library
Added keyframe property to VideoSenderOptions
In the resulting video stream the keyframe property can be set through the `VideoSender`

* keyframe value is given as argument to VideoSender classes and used in VideoStream setup
* motion estimation method is for now deactivated