Updated help in build.cmd. Added -? option that displays the command line syntax. Changed build.cmd to look for NAnt in the PATH and give a usefull error message if it cannot be found.
Updated help in build.cmd. Added -? option that displays the command line syntax.
Changed build.cmd to look for NAnt in the PATH and give a usefull error message if it cannot be found.


git-svn-id: 223c0ba935819ffdcafdc68147dc609b4e469b1e@311972 13f79535-47bb-0310-9956-ffa450edef68

drunkirishcoder/monotouch-log4net,amtkmrsmn/log4net,drunkirishcoder/monotouch-log4net,modulexcite/log4net,Dagwaging/log4net,Dagwaging/log4net,harold4/log4net,harold4/log4net,amtkmrsmn/log4net,StevenJiang2015/log4net,modulexcite/log4net,drunkirishcoder/monotouch-log4net,harold4/log4net,modulexcite/log4net,StevenJiang2015/log4net,drunkirishcoder/monotouch-log4net,amtkmrsmn/log4net,Dagwaging/log4net,StevenJiang2015/log4net