Work in progress for LCSM.

- Added MotifFinder class
- Moved Sequence.FindMotif to MotifFinder.FindMotifIndexes
- Added SequenceEqualityComparer class, implements IEqualityComparer<T>
- Added FindLongestCommonSubsequences to Database
- Added WhereMax<T> methods to LinqExtensions
- Made Solutions.IEV_Solve methods private
Work in progress for LCSM.

- Added Nucleotide.ID and Nucleotide.GetHashCode
- Sequence now implements IEqualityComparer
- Added Sequence.Equals and Sequence.GetHashCode
- Sequence generates it's HashCode on creation and caches it
- Re-factored MotifFinder, still not fast enough for large genetic sequences
Work in progress for LCSM.

- Added LinqExtensions.ContainsSequence
- Added LinqExtensionsTests
- Slight re-factoring to MotifFinder, still not fast enough.
Implemented solution for LCMS.

- Changed Sequence.GetHashCode to use Lazy<int>, generates HashCode when needed
- Changed LinqExtensions.ContainsSequence to use Lists instead of enumerables
- Changed Solutions build options to ignore Robocopy Exit Code 2 (extra files
  found) when building.
Minor re-factor for LCSM.