Just ignore all tarballs
Rename the library to libcangjie

I asked Wan Leung, and he agreed to letting us reuse the name
"libcangjie" instead of "libcangjie2".

This should make life easier for packagers in Linux distributions, as
they can just upgrade their packages instead of having to create new
ones, make them obsolete the old one, play the bureaucracy games of
retiring the old package, etc...

All in all, it just makes more sense, as this is really the follower of
Wan Leung's original library, even though it's a complete rewrite.

We are very grateful to Wan Leung for letting us reuse the name.
Rephrase some comments a bit

Now that we are also called "libcangjie", some references to Wan Leung's
original library did not make a lot of sense any more.

This should make them clearer.
Fixed CLI option error

The options for --use-cj-version (-u) should have been renamed to
--cj-version (-C) in pull request #13. This CLI option renaming,
although implemented in usage() and getopt_log(), was not
implemented in the case switch statement.

This commit is a fix to that.
Merge pull request #38 from yookoala/cli-with-options-fix

Fixed CLI option error
Merge pull request #37 from Cangjians/rename

With the permission of [original libcangjie](https://github.com/wanleung/libcangjie) owner (@wanleung), renaming to libcangjie. The main goal is to simplify packaging issue(s) in distribution.
cli: Add missing copyright header

Can't believe we never had this. o_O
cli: Fix compilation warning

basename() takes a `char *` as its parameter, not a `const char *`.
tests: Drop unused variable
cangjie: Check for errors

We were assuming that everything went just fine and never checking
anything at all.

Baaaaaaad.

Found this with "-Wall -Werror", we should probably try using that more
often! :)
cli: Remove trailing space
Merge pull request #39 from Cangjians/polishing

Polishing