Can't install matplotlib with specific python version

[b5y]

Hi,
Information:

• [+] Matplotlib version: 1.5.1
• [+] Python version: 2.7.11 (pyenv)
• [+] Platform: Linux m 3.16.0-4-amd64 Fix autofmt_xdate() when using in conjunction with twinx() #1 SMP Debian 3.16.7-ckt25-2 (2016-04-08) x86_64 GNU/Linux
• [+] Tried to install matplotlib via pip and in PyCharm with the same python version from pyenv
• [+] Output example:
  
  
  The following required packages can not be built:
  * freetype, png
  
  
  Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-yynSEi/matplotlib/

I can't install matplotlib with these characteristics. I can install in anaconda, but sometimes I need pyenv. I have tried to find information about required packages and found that there is only freetype-py and pypng packages.

[tacaswell]

Just merged a PR to make this clearer #6575

Install freetype-devel and libpng-devel via apt.