Arc-alkali-rydberg-calculator

- fixed bug that caused Numerov not to return result (bd269840f4a5a1b18df6466cd80d3bfe2d240f7e)
- global installation of the package now possible (only on Linux for now) (8e0c51026fdce35585574a1d48eacfc2960244c9)

Note: when using IPython notebook with examples, make sure to set Python kernel same as the Python version of the downloaded package (Python 2.7 or Python 3.5).

New version is **Python 3 and Python 2.7 compatible**. Examples are expanded and documentation corrected. Please download below pre-compiled version for your operating system and your Python version.

**Update 17-08-2017:** if Numerov integration gives 0 for dipole matrix element, please try using fixed version below, or refer to the latest release.

This is version 1.1rc of ARC.

**Recommended installation** is done by downloading below correct pre-compiled package for Windows, Mac or Linux 64-bit machines.

**Advanced** Linux and Mac users can also download the source, and compile C extension, following [Installation instructions](http://arc-alkali-rydberg-calculator.readthedocs.io/en/latest/installation.html#compiling-c-extension). For Windows users, we recommend using pre-compiled binary provided below. Please contact ARC developers if you have problems with that.

Several minor bug U/I fixes, updated Hydrogen class, updated and expanded precalculated databases. Now ships with C instead of C++ code for optimal Numerov calculation, reducing dependencies.

Compiled C++ Numerov calculation now has permission to be executed (chmod 774). This release also corrects issue 1 - now the package contains arc/temp/ folder that allows C++ implementation of Numerov to run without problems.