completion/dotnet: new completion

See: https://docs.microsoft.com/en-us/dotnet/core/tools/enable-tab-autocomplete#bash

completion/available/dotnet.completion.bash

@@ -0,0 +1,18 @@
+# shellcheck shell=bash
+about-completion "bash parameter completion for the dotnet CLI"
+# see https://docs.microsoft.com/en-us/dotnet/core/tools/enable-tab-autocomplete#bash
+
+_dotnet_bash_complete()
+{
+  local word=${COMP_WORDS[COMP_CWORD]}
+
+  local completions
+  completions="$(dotnet complete --position "${COMP_POINT}" "${COMP_LINE}" 2>/dev/null)"
+  if [ $? -ne 0 ]; then
+    completions=""
+  fi
+
+  COMPREPLY=( $(compgen -W "$completions" -- "$word") )
+}
+
+complete -f -F _dotnet_bash_complete dotnet