Add *.xhtm file extension
Add *.xhtm file extension

`xhtm` - is also valid file extension for XHTML files. It is like `htm` and `html` for HTML.
Krzysztof-Cieslak/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,Microsoft/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,Krzysztof-Cieslak/vscode,Microsoft/vscode,Krzysztof-Cieslak/vscode,eamodio/vscode,eamodio/vscode,microsoft/vscode,eamodio/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,Microsoft/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,Microsoft/vscode,microsoft/vscode,eamodio/vscode,eamodio/vscode,Microsoft/vscode,microsoft/vscode,microsoft/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,eamodio/vscode,microsoft/vscode,microsoft/vscode,Krzysztof-Cieslak/vscode,Microsoft/vscode,Microsoft/vscode,Microsoft/vscode,Krzysztof-Cieslak/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,Microsoft/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,microsoft/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,eamodio/vscode,eamodio/vscode,Microsoft/vscode,eamodio/vscode,Microsoft/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode,Krzysztof-Cieslak/vscode,microsoft/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,eamodio/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,eamodio/vscode,Krzysztof-Cieslak/vscode