Clever gitignore for vendor dir

[rugk]

• To the extent possible under law, I have waived all copyright and related or neighboring rights to this PR and publish it as public domain.

This PR fixes the discussion in #65 (comment) (it's a try, at least)

Changes

• Ignore vendor dir only partially, allows all PHP files
• This results in the Composer license file being ignored, so I added it to the general license
• Removed some other unnecessary files, which had something to do with composer
• I explicitly needed to exclude the license files, theoretically we could also explicitly include them, so that we do not need to add them to the general license file.
• Additionally I also excluded test directories. This list can be expanded further.

[rugk]

Example of files, which would be included:

    vendor/EXAMPLE.php
    vendor/paragonie/EXAMPLE.php
    vendor/paragonie/random_compat/lib/EXAMPLE.php
    vendor/yzalis/EXAMPLE.php
    vendor/yzalis/identicon/EXAMPLE.php
    vendor/yzalis/identicon/src/EXAMPLE.php

[rugk]

TravisCI failure is only a broken test in TrafficLimiterTest. These tests seem to be quite unstable...
At least there is nothing wrong with this PR.

[elrido]

Thank you for the cleanup!

One thing: The doc/ folder in my dev environment contains all the generated API docs from phpdoc, similarly to the tst/log/ after running phpunit. Could you revert just that one ignore rule?

[rugk]

Mhh, but our own doc should be included, so I'll try to generate the doc to see how to exclude it in a nice way. Maybe only include Markdown files?

[rugk]

Or well, we could of course also just change this command suggested there: phpdoc -d lib/ -t doc/

[elrido]

Thanks!