.bashrc: Align PS2 with PS1
.bashrc: Don't try to right-align PS2 with PS1

PS1's length can change; as it turns out, calculating the length of
PS1 in bash is difficult, as this incredibly useless Stack Overflow
answer points out [1], so for now don't bother aligning until I can
figure out how to actually do it.

  [1] http://stackoverflow.com/a/15063642/28804
.bashrc: Remove ANSI escape sequence for inverted colors

Inverted is rarely used alone; normally it's part of a set of
attributes including colors.