Hundreds of supporters of equal rights for all Americans gathered this afternoon on the state Capitol's west steps, waving flags and cheering on gay and lesbian couples who have claimed the right to marry, as spelled out by the California Supreme Court.  Political stars such as Senate President pro Tem Darryl Steinberg and Senator Mark Leno joined entertainers Margaret Cho, Wanda Sykes and Star Trek's George Takei and his husband Brad Altman in celebration of equal marriage rights and in anticipation of the upcoming decision by the Supreme Court regarding Proposition 8. The court, located just across the street from the Capitol, will decide the constitutionality of Prop. 8 on March 5. Pr