Add .idc extension for C lexer (#644).
Add .idc extension for C lexer (#644).

aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments,aswinpj/Pygments