Spring v0.81.1282 Fixes, enhancements and optimizations

[Carsten Sachse]

A new version of Spring has been posted at the bitbucket repository:

1. SEGMENTREFINE3D

a) disk requirements for temporary directories revised.
b) improved handling of selected segments. Spring processes helices as one entity and discards them later for 3D reconstruction.
c) FSC only computed with cylinder mask.
d) Improved experimental power spectra for high/maximum resolution analysis.
2. SEGMENT
a) fix in frame processing.
b) rotated stack only written if requested.
3. SEGMENTEXAM now with selection options from spring.db.
4. SEGCLASSEXAM now with mpi option.
5. SEGLAYER2LATTICE now includes tooltips of predicted Bessel orders.
6. SEGCLASSLAYER
a) now accepts also power spectra.
b) includes tooltips on Bessel look up table.
7. Parameter input from prompt now works using Tab auto completion including file search.