STLplus C++ library collection SVN stlplus3

Added conditional make of tests if present

Tidied up error handling in subprocess classes

Tidied up error handling in subprocess classes

Proper use of the getcwd function

Blocked SIGPIPE on Linux

Make the makefile call make_monolithic if necessary. Likewise with target clean, call unmake_monolithic.

Added access method for the environment that the child was executed in

Test for the subprocess classes

Removed tesxt that had somehow been accidentally pasted into the document

Added access methods to read the environment that the subprocess was
spawned with. Fixed bug in backtick subprocess where the buffer last
element could be accessed when the buffer was empty.