Improve buildbot script

PR created under the employment of EvidenceBKidscode

* Variables to set git repositories urls (allows to build from another repo)
* Variables to set git branch to build from (allows to build from non-master branch)
* Variables to change built name
* Make -j uses the proper number of processors (autodetect)
* Changed toolchain from win32 to adpat it to non-debian distros

.travis.yml

@@ -34,22 +34,10 @@ matrix:
     - env: PLATFORM=Win32
       compiler: gcc
       os: linux
-      addons:
-        apt:
-          packages: ['gcc-mingw-w64-i686', 'g++-mingw-w64-i686', 'binutils-mingw-w64-i686']
-          sources: &sources
-            - ubuntu-toolchain-r-test
-            - sourceline: 'deb http://mirrors.kernel.org/ubuntu xenial main universe'
 
     - env: PLATFORM=Win64
       compiler: gcc
       os: linux
-      addons:
-        apt:
-          packages: ['gcc-mingw-w64-x86-64', 'g++-mingw-w64-x86-64', 'binutils-mingw-w64-x86-64']
-          sources: &sources
-            - ubuntu-toolchain-r-test
-            - sourceline: 'deb http://mirrors.kernel.org/ubuntu xenial main universe'
 
     - env: PLATFORM=Unix
       compiler: clang