Review all doc examples/code for best-practices for output / sanitization

[PodsBot]

Review all doc examples/code for best-practices for output / sanitization submitted via Slack by sc0ttkclark

[sc0ttkclark]

We should review our docs/examples to ensure best-practices are utilized.

Output escaping:

• esc_attr when outputting field values into HTML attributes
• esc_html when outputting field values but to escape the HTML characters
• Some field types strip HTML tags (some or all) and do other things, so it's not a huge issue except when people use echo $pod->field( 'field_name' ) since display() is where that logic runs

Input sanitization:

• sanitize_text_field when sanitizing values coming from a form or external source, this removes HTML and line breaks
• pods_sanitize when sanitizing values for the database

[jimtrue]

We'd also need to know anyplace we do escaping of stripping of attributes in our code output as well, so we can highlight it's not necessary to escape those beforehand.