Always use Add Rec LoadPath to set up Charge!'s load path

This makes it possible to play around with alternative ways of arranging
Coq projects
Added some error reporting during Java proof initialisation

Bailing out during initialisation leaves coqtop in an unknown state. It
might be possible to fix this by using the BackTo command
Corrected the signature of the CoqTopIdeSlave_v20120710.set_options method

This commit also fixes a strange bug in the implementation of that method
Added basic transaction support to CoqTopIdeSlave_v20120710

This commit adds a method which automatically rolls back all Coq commands
executed by a function if any of them fail
Use the new transaction support code to perform Java proof initialisation

If an error occurs during Java proof initialisation, coqtop will now be
left in a sensible state, which is nice
Use the new transaction support code to perform Coq proof initialisation

This code is less interesting than the Java initialisation code, so error
reporting isn't as useful here -- but consistency is good!
Simplified some unnecessarily-complicated bits of code

This commit also gratuitously changes the default colour used for marking
underway proof fragments
Deleted the CoqJavaProject and EclipseBoilerPlate classes

EclipseStuff was once 1500 lines long. How times have changed
Added a GoalPresenter implementation which displays hypotheses in a table

GoalViewer doesn't yet support changing the presenter, but it will soon
Added support for changing a GoalViewer's presenter
Added drop-down menu options for changing the active goal presenter