Cleanup of linux autogenerated files

[M-F-K]

• currently we have 3 related "makefiles" instead of a single one. This goes for all the folders that needs to build something. We should remove the ones not needed, - as far as I know we only needs the Mikefile.am ones.
• There is a lot of auto-generated files committed in the indielib/linux folder, - we need to remove some so that we only have the ones that are not autogennerated.
• The *.plo build files should be ignored by the repository.

[M-F-K]

The makefiles part is now fixed.

[M-F-K]

Abot the 3rd bullet, we probably should add a global ignore file, - read more here: https://help.github.com/articles/ignoring-files

2 files, that needs to be merged into the result are:

• https://github.com/github/gitignore/blob/master/C%2B%2B.gitignore
• https://github.com/github/gitignore/blob/master/Autotools.gitignore

[M-F-K]

Have cleaned the makefiles, have added a .gitignore file, have generally cleaned up the linux path, - think we can close this issue (if I have forgotten some files, we can clean these when we encounter them).

Closing this issue.