Small fix in DEVGUIDE.html docu

- If we work the DEVGUIDE step-by-step we will be in /src
- In order to get to tests we need to step out
Adding links to Perl and NUnit in DEVGUIDE.html
Refactoring the ILComparer tool project so that it can build from source, instead of requiring a checked-in binary (changeset 1225430)
Move the hosted compiler infrastructure over to the open repo and refactor projects so that it builds from source rather than requiring a checked-in binary. (changeset 1225435)
Add required plumbing so that one can build FSharp.Core for portable profile 47 in open repo (Requires rebuild of Proto so that portable targets file gets dropped) (changeset 1225504)
Add script to build test tools from source (changeset 1225556)
Allow user to specify what build flavor they want to run tests against, debug or release. (changeset 1225561)
Update docs to reflect recent changes (changeset 1225564)
Fixing defines for portable profile 47 FSharp.Core to align with what ships in Visual Studio F# (changeset 1226720)
Reconfiguring a bunch of tests that were hard-coded to use Visual Studio paths to find FSharp.Core and other F# bits.  They will now use open-built bits when run from an open repo. (changeset 1226736)
Fixing a couple of typos from the previous checkin (changeset 1226793)
Use folders in FSharp.Compiler.fsproj
remove non-existent file in solution
Add folders to FSharp.Core.fsproj
Add strong name validation skip for test library FSharp.Compiler.Hosted (changeset 1227695)
Update open build to target .NET 4.5 and MSBuild 12.  This aligns the open build with what ships in VS 2013 and F# 3.1.1 OOB.

Also stripping out some unnecessary configuration checking - 'net40' is the only supported TargetFramework for building the compiler, build libraries, and type providers. Only FSharp.Core supports other target platforms. (changeset 1227697)
Fixing typo in TESTGUIDE
chmod u+x on run-opt.sh
Update .travis.yml
update targets to build PCL with 3.4.0 and 3.2.7