Tagged template formatting support

[dsherret]

Tagged templates should be able to format with the host formatter similar to how things work for code blocks in dprint-plugin-markdown.

Related issues:

• Format html tagged template text #9
• styled-components support  #643

[g-plane]

I think we can put the host formatter closure into Context struct, but this closure needs to be passed via:

• dprint-plugin-typescript/src/generation/generate.rs

  Line 34 in 45b3bd9

  let mut context = Context::new(parsed_source.media_type(), parsed_source.tokens(), program_node, program, config);

• dprint-plugin-typescript/src/generation/generate.rs

  Line 28 in 45b3bd9

  pub fn generate(parsed_source: &ParsedSource, config: &Configuration) -> PrintItems {

• dprint-plugin-typescript/src/format_text.rs

  Line 73 in 45b3bd9

  fn inner_format(parsed_source: &ParsedSource, config: &Configuration) -> Result<Option<String>> {

• dprint-plugin-typescript/src/format_text.rs

  Line 64 in 45b3bd9

  pub fn format_parsed_source(source: &ParsedSource, config: &Configuration) -> Result<Option<String>> {

• dprint-plugin-typescript/src/format_text.rs

  Line 42 in 45b3bd9

  pub fn format_text(file_path: &Path, file_text: String, config: &Configuration) -> Result<Option<String>> {