[REQS-249] Out of bound exception
[PLAT-6655] Matrix computation for portfolio hedging calculator

Also includes [PLAT-6656] example tests
[PLAT-6656] Examples of portfolio hedging calculation
[PLAT-6655] Tidy up matrix calculator code
[REQS-403] Created example of swap build with Annuity Builders.
[REQS-403] Added more examples of swaps. Curve can be standard curves or IMM based curves.
[REQS-403] Added example on GBP curves and OIS. Started documentation on the tutorials.
[REQS-403] Added documentation for tutorial.
[REQS-403] Added Fed Fund swap curves.
[REQS-403] Added curves based on Fed Fund swaps for swap risk analysis in tutorials.
Update release notes
PLAT-6665 InMemorySecurityMaster replace() fails if UniqueId missing
Bump version to 2.4.0-SNAPSHOT
Update release notes
Merge pull request #131 from OpenGamma/topic/PLAT-6665

PLAT-6665 InMemorySecurityMaster replace() fails if UniqueId missing
[PLAT-6666] Linear interpolation instead of simple average
[PLAT-6666] Using ArgumentChecker per review
[PLAT-6666] Removing unused code
PLT-398 - Intern stack trace when constructed by Joda beans builder
[PLAT-6666] Using TimeCalculator per review