Merge pull request #44 from herbygillot/patch-1

README: add MacPorts install info

README.md

@@ -104,7 +104,7 @@ an initial correct regex which should be inspected by hand if further optimizati
 
 You can download the self-contained executable for your platform above and put it in a place of your choice. 
 Alternatively, pre-compiled 64-Bit binaries are available within the package managers [Scoop](https://scoop.sh) 
-(for Windows), [Homebrew](https://brew.sh) (for macOS and Linux) and [Huber](https://github.com/innobead/huber) (for macOS, Linux and Windows). 
+(for Windows), [Homebrew](https://brew.sh) (for macOS and Linux), [MacPorts](https://www.macports.org) (for macOS), and [Huber](https://github.com/innobead/huber) (for macOS, Linux and Windows). 
 [Raúl Piracés](https://github.com/piraces) has contributed a [Chocolatey Windows package](https://community.chocolatey.org/packages/grex).
 
 *grex* is also hosted on [crates.io](https://crates.io/crates/grex), 
@@ -114,7 +114,7 @@ toolchain installed, you can install by compiling from source using
 So the summary of your installation options is:
 
 ```
-( choco | scoop | brew | cargo | huber ) install grex
+( choco | scoop | brew | cargo | huber | port ) install grex
 ```
 
 ### 4.2 <a name="how-to-install-library"></a> The library <sup>[Top ▲](#table-of-contents)</sup>