Pyenv

* python-build: Fix build error of CPython 2.x on the platform where the `gcc` is llvm-gcc.

* pyenv: Reliably detect parent shell in `pyenv init` (93)
* pyenv: Import recent changes from rbenv 0.4.0
* pyenv: Import `bats` tests from rbenv 0.4.0
* python-build: Add new CPython releases candidates; 3.4.0b2
* python-build: Add ruby-build style patching feature (91)
* python-build: Set `RPATH` if `--enable-shared` was given (65, 66, 82)
* python-build: Update default setuptools version (2.0 -> 2.1)
* python-build: Update default pip version (1.4.1 -> 1.5)
* python-build: Activate friendly CPython during build if the one is not activated (8fa6b4a1847851919ad7857c6c42ed809a4d277b)
* python-build: Fix broken install.sh
* python-build: Import recent changes from ruby-build v20131225.1
* version-ext-compat: Removed from default plugin. Please use [pyenv-version-ext](https://github.com/pyenv/pyenv-version-ext) instead.

* python-build: Fix broken build of CPython 3.3+ on Darwin
* python-build: Not build GNU Readline uselessly on Darwin

* python-build: Add new CPython releases; 3.3.3 (80)
* python-build: Add new CPython releases candidates; 3.4.0b1
* python-build: Add new PyPy releases; pypy-2.2.1, pypy-2.2.1-src
* python-build: Update default setuptools version (1.3.2 -> 2.0)
* python-build: Imported recent changes from ruby-build v20131211
* pyenv: Fix pyenv-prefix to trim "/bin" in `pyenv prefix system` (88)

* python-build: Add new CPython releases; 2.6.9, 2.7.6 (76)
* python-build: Add new CPython release candidates; 3.3.3-rc1, 3.3.3-rc2
* python-build: Add new PyPy releases; pypy-2.2, pypy-2.2-src (77)
* python-build: Update default setuptools version (1.1.6 -> 1.3.2)
* python-build: Imported recent changes from ruby-build v20131030

* pyenv: Improved [fish shell](http://fishshell.com/) support
* python-build: Add new PyPy releases; pypy-2.1, pypy-2.1-src, pypy3-2.1-beta1, pypy3-2.1-beta1-src
* python-build: Add ancient versions; 2.4, 2.4.1, 2.4.3, 2.4.4 and 2.4.5