Added dos2unix programs to convert line endings from dos/windows to
unix.

Hopefully this fixes the issues reported by johr in issue #45 and issue #50
reported by Limpster.
Replaced dos2unix call with call to local function sanitize_inputfile().

This makes it more generic and if more processing of input files is
needed, it will only need to be done in one place.
Fixed variable assignment by removing spaces.
Cleaned up files needed/used for inputfile sanitization.

Removed unix2* programs since they won't be needed.
Replaced mac2unix with a symbolic link to dos2unix, since that's what it is
in the package as well.
Removed the dos2unix package and programs from the installer image.

They're already part of busybox, so no need to add them (again).
Fixed some output (formatting) inconsistencies.
Fixed the rest of the formatting inconsistencies and made the logging a
bit more verbose.
Add root login workaround for jessie.

The default value of openssh-server of PermitRootLogin has changed in
jessie, which made users trying to install jessie unable to login to
their system. This workaround restores the old situation and thereby
fixes #45.

Proper solution is adding support for key-based authentication.
Updated README for v1.0.1 release and corrected various issues.
Don't abort installation when 'apt-get update' encounters an issue.

Hopefully it always works, but it's not a fatal issue. When it could be
a problem, we should deal with it the best we can.
Don't abort installation when firmware fails to install, only report it.
Hard code raspberrypi.org release to wheezy in sources.list.

While raspbian does support multiple releases (wheezy and jessie atm),
the raspberrypi archives do not.
Therefor hard code wheezy for the raspberrypi.org archives.
Place downloading of package files into its own function.

This will make it easier to make it more robust by trying various urls
if one compression format is not supported (anymore).
Added support for various compression formats for Packages download.

Now xz (apparently the new default), bzip2 and gz are supported.
Changed ntp name from OpenHTPd to NTP in documentation.
Make explicit that rootsize should be specified in megabytes.
Fixed some minor issues with the documentation.
Fixed some markdown formatting issues.

To force a line break, you have to add 2 spaces at the end.
Fixed the check whether a new kernel is installed.

This fixes an issue when cdebootstrap_cmdline is specified in
installer-config.txt, in which case a whole code path is skipped.
Thanks to gabrielrm from the forums for bringing that to light.
Replaced hardcoded kernel version with variable.

Closes #59