Problems with multiple sections

[skutsaev]

1. Multiple section don't work correctly
2. Phase shift is not working correctly.
3. Verify that when simulating the linac with 2 sections with different frequencies, the bunch length doesn't change with the frequency change (i.e. x/lmb1 != x/lmb2 but x/lmb2 = x/lmb1 * lmb2/lmb1)

[bruhwiler]

@skutsaev -- if the frequency is the same in two linac sections, is there still a problem?

[bruhwiler]

@skutsaev -- please make this your next priority.

[skutsaev]

Fixed