Refactored parsing of macros
Fixed fatal error for unknown macro
Added support for named arguments for macros
Added support for directly call macros defined in the same template
Fix for {% embed %} error line number bug
merged branch h2s/embed-error-line (PR #1140)

This PR was squashed before being merged into the master branch (closes #1140).

Discussion
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Fix for {% embed %} error line number bug

This deals with issue #958. I've gone into a lot of detail about the fix itself in the commit message for 12cc0a0, so I won't repeat any of that here. Take a look and let me know what you think!

Commits
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270b791 Fix for {% embed %} error line number bug
updated CHANGELOG
prepared the 1.13.2 release
bumped version to 1.14.0-DEV
merged branch hason/macros (PR #1139)

This PR was merged into the master branch.

Discussion
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Improved macros

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #861, #867, #929, #1052
| License       | MIT
| Doc        | yes

* Fixed fatal error for unknown macro
* Added support for named arguments for macros
* Added support for directly call macros defined in the same template

Commits
-------

3004ba1 Added support for directly call macros defined in the same template
63615a6 Added support for named arguments for macros
09fedb8 Fixed fatal error for unknown macro
9e96837 Refactored parsing of macros
updated CHANGELOG
added an exception when a macro re-uses the same argument name twice
renamed an internal variable
fixed some unit tests
unified LICENSEs between the PHP and the C code
added a note about how to use our PEAR channel to install the Twig C extension
fixed a bug in some unit tests (closes #1092)
fixed the filesystem loader cache when a template name exists in several namespaces
tweaked documentation about overloading existing filters, ... (closes #1094)