Introduced incremental versioning from git tag and -r option to ndpiReader to print revision

[lucagiove]

Version is now extracted using git describe --tags --long --dirty --always this uses the last git tag as version then an incremental number that reflects the number of commits (like svn revision) plus the commit hash:

1.5.2-43-gb3a292d-dirty
^     ^  ^        ^
|     |  |        |
|     |  |        if there are uncommitted changes
|     |  SHA of HEAD
|     number of commits since last tag
last tag

This allows to have incremental versioning changing at each build like it was before with svn.

Also added a -r to print ndpiReader / nDPI version and revision.
(I would have rather preferred -V or --version that is standard but I didn't want to change too much the code)

ntop@bs-ndpi:~/target/bin$ ./ndpiReader -r
ndpiReader, nDPI (1.5.2-45-gb3b0ce7)

[lucagiove]

Great ;) consider that you need to add at least one tag.
On my branch I did this:

git tag 1.5.2 2e5ceac844c32fb52f4f3042be5b872f8b0b4ff0
git push --tags

[lucaderi]

I am patching the code. Hold on.