further jedit build option; misc tuning;

build jedit as part of regular startup script (in that case depending on jedit_build component); misc tuning and simplification;

updated headers;

moved sources -- eliminated Netbeans artifact of jedit package directory;

removed obsolete Netbeans project setup;

support fresh build of jars; prefer pushd/popd, to avoid unclarity about fail/exit within sub-shell;

more jvmpath wrapping for Cygwin;

more robust exception pattern General.Subscript;

pervasive Output operations;

modernized Proof_Context;

standardized header;

merged