Add "Quick Fix" for adding missing required parameters

[thso]

When a template function call is missing required parameters

{template .foo}
  {@param a: int}
  {@param b: text}
{/template}

{template .other}
  {let $a: 42 /}

  {call .foo<caret>}
  {/call}
{/template}

a quick fix should add them

{template .other}
  {let $a: 42 /}
  {call .foo}
    {param a: $a /}
    {param b kind="text"}

    {/param}
  {/call}
{/template}

Notes:

• Default is to add the block parameter composed of open and close tags,
• If there is variable in scope with a name that matches one of the parameters then create a self-closing parameter tag that passes through that variable

[kaathewise]

blocked by #91

[thso]

Not doing this.