Add validation to some of the fields in the Debian control file

Add validation to some of the fields in the Debian control file 

In order to avoid breaking changes, we need to add validations only to cases that breaks the client.

You can find the client validation code in https://github.com/Debian/apt/blob/master/apt-pkg/deb/deblistparser.cc

Here are the main errors that the client throws:

"Encountered a section with no Package: header"

"Malformed Description-md5 line; doesn't have the required length"

"Malformed Status line"

"Malformed status line, no 2nd word"

"Malformed 2nd word in the Status line"

"Malformed Status line, no 3rd word"

"Malformed 3rd word in the Status line"

"Problem parsing dependency"

"Problem parsing Provides line of"