Make readme.md say that all versions starting with 2015 are supported

readme.md

@@ -1,6 +1,6 @@
 # posh-vs
 
-Makes Visual Studio command line tools available in PowerShell. Supports Visual Studio 2017 and 2015.
+Makes Visual Studio command line tools available in PowerShell. Supports Visual Studio 2015 and later versions.
 
 ## Usage
 
@@ -20,7 +20,7 @@ PS> . $profile
 ```
 
 Use Visual Studio command line tools in PowerShell:
-``` 
+```
 PS> msbuild /?
 ```
 
@@ -29,10 +29,10 @@ PS> msbuild /?
 `Install-PoshVs` adds an `Import-VisualStudioEnvironment` call to the PowerShell
 [profile](https://msdn.microsoft.com/en-us/powershell/reference/5.1/microsoft.powershell.core/about/about_profiles).
 It will import the environment variables set by the `VsDevCmd.bat` of the latest version of Visual Studio installed
-on your computer. If multiple instances of Visual Studio 2017 are installed, `Import-VisualStudioEnvironment`
+on your computer. If multiple instances of Visual Studio are installed, `Import-VisualStudioEnvironment`
 will use whichever instance happens to be listed first.
 
-To use a specific instance of Visual Studio 2017, manually change your profile to import a specific batch file.
+To use a specific instance of Visual Studio, manually change your profile to import a specific batch file.
 ```
 Import-BatchEnvironment 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\Tools\VsDevCmd.bat'
 ```
@@ -68,6 +68,6 @@ PS> Invoke-psake
 
 ## Credits
 
-posh-vs was inspired by [Alen Mack](http://allen-mack.blogspot.com/2008/03/replace-visual-studio-command-prompt.html), 
+posh-vs was inspired by [Alen Mack](http://allen-mack.blogspot.com/2008/03/replace-visual-studio-command-prompt.html),
 [StackOverflow contributors](http://stackoverflow.com/questions/2124753/how-i-can-use-powershell-with-the-visual-studio-command-prompt)
 and [posh-git](https://github.com/dahlbyk/posh-git).