Added splash screen, downgraded .net version & code fix wrt CA2202

Downgraded .net version to 4.5 from 4.5.2 primarily because, a lot of
users, won’t have it pre-installed, and so it becomes kinda clunky for
them, to also install .net 4.5.2
Also, a code fix was done in Searcher.cs wrt to CA2202 -
http://msdn.microsoft.com/query/dev12.query?appId=Dev12IDEF1&l=EN-US&k=k
(CA2202);k(TargetFrameworkMoniker-.NETFramework,Version%3Dv4.5)&rd=true