T.D. your right, the correct analysation (?) of that would be 5 of 2 to the 2 to the 5 to the 1. The E-7 would be the 2 chord of the A7 (its common practice in jazz to insert a minor 7th chord before a dominant). This is also known as back-cycling, approaching your destination chord (Cmaj7) in root movements of 5ths (G is the 5 of C, D the 5 of G, A the 5 of D,& E the 5 of A). But most jazz players just refer to this progression as a 3 6 2 5.

Lali..a picardy 3rd is when you change the maj4 chord into a minor. Ex; D C C- G