Add secure bootstrapping script for GLBackend.

This implements the issue described in #96
fixed a bug on Linux #92
Fix md5 verification to work with GNU md5sum
approached a bug happening in installation without jpeg-dev
Implement log file rotation.

By default we rotate every 1M and up to a maximum of 100 files (100MB).
This fixes https://github.com/globaleaks/GlobaLeaks/issues/108
solved/removed all the TODOs
Merge branch 'issue/96' of github.com:globaleaks/GLBackend into issue/96

* 'issue/96' of github.com:globaleaks/GLBackend:
  fixed a bug on Linux #92
Merge pull request #93 from globaleaks/issue/108

Implement log file rotation.
fixed logs and few bugs again
Merge pull request #94 from globaleaks/bug/installation-jpeg

Bug/installation jpeg
file upload max size: https://github.com/globaleaks/GlobaLeaks/issues/109
temporary fix to https://github.com/globaleaks/GlobaLeaks/issues/116
implemented the same temporary fix to other situations (https://github.com/globaleaks/GlobaLeaks/issues/116)
bootstrap script updated to handle Globleaks main repository.
Merge pull request #92 from globaleaks/issue/96

Add secure bootstrapping script for GLBackend.
cleaned fdesc and fixed a reference bug
added --version and version info in /node API
restored mail_exception and cyclone_debug
more exception handling and bug solving of cyclone_debug + file upload
scripts/sbootstrap.sh removed and moved to https://github.com/globaleaks/GlobaLeaks/blob/master/install.sh