remove superfluous padding added by normalize-indels

a) when nothing normalizes, don't change the entry at all
b) when things do move, only add padding if one of the resulting
alleles would be empty
update tests for new normalization behavior
move string algorithms out of Sequence.hpp
add common{Prefix,Suffix}Multi functions

to find the longest commen prefix/suffix of a bundle of strings
simultaneously (e.g., of all alt alleles in a vcf record)
alt normalizer refactoring -- part 1
alt normalizer refactoring -- part 2
fix infinite loop in commonPrefixMulti

when asking for the common prefix of 0 strings
add unpadded start/stop functions to vcf entry
add CoordinateView abstraction

This lets us specify a type to extract chr/start/stop from objects. The
first use is to have a version that extracts raw positions from a vcf
entry and another that extracts unpadded coords.
update GroupOverlapping to use CoordinateView
remove execute method from GroupOverlapping

now it gets used via streampump
gcc4.4 fixes :(
add LocusCompare object

to order objects with chr/start/stop
allow GroupOverlapping to take a vector of entry ptrs
remove cmp functions from Bed class
add boost tti and boost heap
big update to datatype comparison operators

variant entries no longer have cmp / operator< functions. The use
LocusCompare objects intead
reorganize new relops code
generalize sorting of unique_ptrs on compilers that suck
remove stray typename