Popular social coding and code hosting site GitHub is close to make an fund raising agreement with venture capital firm Andreessen Horowitz. After this round of fund raising, GitHub's market value will be around $500-800million.GitHub is a very popular social coding website, the major clients are programmers from big IT companies. Recently, GitHub even becomes a platform for some big companies to recruit new programmers, some HR managers are more willing to read applicant's GitHun profile instead of just the personal resume.Since launched in 2008, GitHub has over 1.6 million registered users a...