allow more than one author and change some styles in blog post

[curibe]

• allow to check if there is one or mre authors
• change the author's profile from h4 to h5 when there are more than one
• change/rewrite some styles to put the author and hiring-newsletter in columns for small displays

before responsive adjustment

with one author in responsive

with two author in normal screen

with two authors in responsive

[juanArias8]

@curibe responsive is not working for some media queries