Add unit test on empty test for string "0"
Fixes bug introduced in #633
Added 'extra-cflags','extra-libs' and 'package-dependencies' to config.json that zephir supports compile and link with external-libraries.

Signed-off-by: Rack Lin <racklin@gmail.com>
Fixes indent

Signed-off-by: Rack Lin <racklin@gmail.com>
Merge pull request #636 from racklin/pkgconfig

Added Zephir supports compile and link with external-libraries
Fixes #635
Fix type hints in stubs
Removing protected underscore prefix
Merge branch 'master' of http://github.com/phalcon/zephir
Merge pull request #638 from rzajac/stubsTypeHintFix

Stubs type hint fix
Merge pull request #631 from vpg/emptyString

[BUG] empty operator bug with string "0"
Merge branch 'master' of http://github.com/phalcon/zephir
Removing prefixed protected properties
Fix empty test to make it work as in PHP
Fixing coding style, raising a warning when a wrong type is paseed to a statically-typed parameter
Fixes invalid bind of this in closures, improved wrong parameter pass detection
LetStatement and NativeArray - array can be empty
Merge pull request #641 from ovr/empty_native_array

LetStatement and NativeArray - array can be empty
Existence and visibility of properties was not being verified in certain types of mutations
Reference to system headers by <...>