issue38
Now --print adds spaces to the output correctly.

Issue #25
Order of methods corrected.

`remove_file' methods was between two `import_file'.
Documents updated.

`remove_file' added to the API reference.
`--print' completed in the CLI reference, and `--remove' added to it.
Versions updated.
In `create_file', auto releasing VM was commented out by mistake.
Tocc's web site and my e-mail address corrected in all copyright notices.
API : set title to a group of files
API : update Manager::set_titles() comment
CLI : change set-title command's error message +  support to set title to a group of files
CLI : update set-title help message + correct the command's error message
Merge branch 'issue38' of https://github.com/hlyassine/tocc into yassine-issue38
Memory management fixed.

Issue #31
I removed all `create' methods, and now each expression copies all
the objects passed to its constructor.
Now Query accepts a reference in its constructor instead of a pointer.

Issue #23
Tests modified according to new structure of experssions.

Issue #23
Destrcutor of Expr was protected. Changed to Public.

Issue #13
Structure of Expressions changed in libtocc. CLI changed respectively.

Issue #13
update
Merge branch 'issue38' of https://github.com/hlyassine/tocc into yassine-issue38
Merge branch 'yassine-issue38'

issue #38 and pull request #57