model: Small extension of printing out entries of the content store
(printing more specific data for specialized versions of the content stores)
tests: Fixing issue #31 related signed/unsigned comparison warning in one of the tests
model: Add use of "extern template" to prevent duplicate instantiation/initialization of templated classes

This syntax has been tested with gcc and clang, but may not be fully
supported by other compilers.  Additional testing (and optional ifdef
blocks) is required for the final solution to the problem.
examples+docs: Adding a new example to print out instantaneous PIT sizes periodically
apps: Solving a serious bug #33 in ndn::ConsumerWindow

In certain cases, the number of in-flight packets was maintained in a
wrong way, creating inconsistencies and incorrect decision on when to
send out a new Interests.  That is, the number of in-flight
packets could be non-zero, while there were no outstanding packets at all.

Thanks to Cheng Yi for the bug discovery
model: Small modification in BestRoute strategy

There is no real need to call parent's (green-yellow-red strategy's)
DoPropagateInterest method, since everything what it is doing is already
incorporated in the logic of the BestRoute strategy.

closes #32
bindings: Rescanned python bindings
topology-reader: Adding support for adding and configuring ErrorModel on each link

Thanks to Saran Tarnoi for the initial implemenation
model: Add ability to get pointer to Fib from fib::Entry
Merge feature branch 'feature/topology-reader-error-model'
docs: Adding research papers section to ndnSIM website
model+tracers: Implementing ability to trace satisfied/timed out interests

Implementing satsified/timed out interest tracing in L3AggregateTracer and L3RateTracer (only numbers)
model: Add ns3::ndn::Pit::MaxPitEntryLifetime to configure maximum time for which routers are willing to accept any incoming interest

Actual PIT lifetime should be minimum of MaxPitEntryLifetime and
InterestLifetime specified in the Interest packet.
model: Huge bug with ndn::pit::Entry

Not setting PIT entry lifetime in the constructor resulted in immediate
removal of the PIT entries in some cases.  Reverting back behavior
changed by the previous commit.
build: Update wscript for waf-1.7.x
build: no longer require fake `ns3' directory in NS-3's root folder
python bindings: Rescanned
apps: Fixing bug with ns3::ndn::ConsumerWindow::InFlight trace source

Thanks to Junxiao Shi for catching the bug.

closes #34
apps: Fixing bug with randomization configuration of ndn::ConsumerCbr

Thanks to Junxiao Shi for reporting the bug.

fixes #35
build: allowing compilation with boost 1.46; removing requirement of boost-iostream library, requiring boost-graph library