test/runutil.vim: minor dictionary key renaming
test/base.vim: added support for var 'g:evlib_test_outputfile'
test: improved test running method and capabilities

 * test/runutil.vim:
  * improved filename and argument "escaping";
  * EVLibTest_RunUtil_Command_RunTests():
   * added '-v' ("verbose") command option;
   * improved "silent"-ness of ex commands that are related to the test
      running and processing (it's (almost?) entirely silent now);
   * test running:
    * improved system to use a "test runner" ('test/testrun.vim') script
       (see change comments for that file, below);
     * side effect: should now be more portable (but testing on other
	platforms has not been done yet);
    * (optionally) specifies a 'debug' flag so that each vim execution
       can report more detailed debug messages;

 * test/testrun.vim (new file):
  * can produce "debug" messages for fine-grained troubleshooting;
  * takes care of setting up redirection (but does not do it yet);
  * 'source's the "test script", and catches (and reports) exceptions;
test/testrun.vim: improved error handling and script folding;
test: minor structural refactoring. increased test format independence.

 * test/base.vim:
  * made this script "test output format agnostic":
   * removed depedency from 'evtest/proc/evtstd/c-defs.vim';
   * removed functions:
    * s:EVLibTest_TestOutput_GetFormattedLinePrefix();
    * s:EVLibTest_TestOutput_OutputLine();
  * added s:EVLibTest_Local_fnameescape();
   * refactored code to use this function instead of the simpler
      "fnameescape() or nothing" method used before;
   * exported through the 'f_fnameescape' Funcref dictionary entry;

 * test/common.vim:
  * added a few comments to document the refactoring done in this commit
     (and a few items to be implemented later);
  * added direct dependency on 'evtest/proc/evtstd/c-defs.vim';
   * NOTE: previous commit was indirectly dependant on this file, as it
      was including 'test/base.vim', which included this file -> the
      file dependency "reachable tree" has not changed;
   * moved the actual function implementation from 'test/base.vim' into
      this script for the following functions:
    * s:EVLibTest_TestOutput_GetFormattedLinePrefix();
    * EVLibTest_TestOutput_OutputLine();
  * removed responsibility of dealing with "test output file
     redirection" from this file:
   * note: removed call to EVLibTest_TestOutput_InitAndOpen();
   * it's now handled by 'test/testrun.vim', to free other test scripts
      (outside of 'evlib'/'evtest') from the responsibility of dealing
      with this issue;

 * test/testrun.vim:
  * includes 'test/base.vim' to get "test output file redirection"
     support;
  * changed to take responsibility of dealing with "test output file
     redirection", to free all test scripts from having to deal with
     that;
   * test scripts can now merely use (for example) ':echomsg' (see ':h
      :redir', ':h :echomsg') to have their output recorded in the "test
      output file";
test: refactoring: added context info support. improvements & fixes.

 * test/base.vim:
  * added support for "debugging messages";
   * improved adhoc debugging messages for calls to s:DebugMessage();
  * added support for sourcing "processor" scripts and invoking their
     functions:
   * moved code from 'test/runutil.vim' (and made modifications to it):
    * s:EVLibTest_RunUtil_Local_GenUserScript_ClearVars() ->
       s:EVLibTest_GenUserScript_ClearVars();
    * s:EVLibTest_RunUtil_Local_GenUserScript_Source() ->
       s:EVLibTest_GenUserScript_Source();
    * s:EVLibTest_RunUtil_Local_ProcessorDef_Invoke() ->
       s:EVLibTest_ProcessorDef_Invoke();
  * added high-level "processor" function wrappers:
   * s:EVLibTest_ProcessorDef_Invoke_WriteTestContextInfo();
   * s:EVLibTest_ProcessorDef_UserCall_WriteTestContextInfo();
 * exported the above functions through s:evlib_test_base_object (then
    assigned to g:evlib_test_base_object_last);

 * test/evtest/proc/evtstd/v0-1-0.vim:
  * added function
     b:EVLibTest_Processor_Invoked_evtstd_TestOutput_WriteTestContextInfo()
     (exported as key 'f_writetestcontextinfo'), to create the test
     context info output in a central place;
  * added 'FIXME:' comments, to be implemented later;

 * test/runutil.vim:
  * changed way in which "processor" functions are invoked: we do so
     directly now (as the functions defined through
     s:Local_DefineFunctionFromFuncRef() did not seem to work
     consistently);
  * fixed: s:evlib_test_base_object.f_testoutput_initandopen() now
     specifies the test output file (l:test_output_file), as the vim
     instance running this function would not (necessarily) have the
     variables defining which file to use for test output;
  * added support for writing "test context info" at different stages
     through the test execution algorithm;
  * improved comments;
   * marked dead code to be removed in a later commit (as it has new
      code that, as the function(s) is(/are) now unused, makes no sense
      to keep in the longer term);
    * to be removed: s:Local_DefineFunctionFromFuncRef();
     * removed its callers, as they would not consistently work (only
        sometimes, and not predictably);
  * added high-level (script-local) test output functions:
   * s:EVLibTest_RunUtil_Local_TestOutput_InvokeWithRedir_Start();
   * s:EVLibTest_RunUtil_Local_TestOutput_InvokeWithRedir_End();
   * s:EVLibTest_RunUtil_Local_TestOutput_WriteTestContextInfo(): uses
      the above functions to enable redirection for the duration of the
      "invoked" function only;
  * as noted in the comments for 'test/base.vim': moved code to that
     file;
  * removed "dead" comments ('prev: ');

 * test/testrun.vim:
   * added test "processor" (convenience) functions:
    * s:EVLibTest_CurrentProcessor_GetInstance();
    * s:EVLibTest_CurrentProcessor_Invoke();
    * s:EVLibTest_CurrentProcessor_UserCall_WriteTestContextInfo();
    * s:EVLibTest_CurrentProcessor_UserCall_WriteTestBlankLine();
  * added support for writing "test context info" at different stages
     through the test execution algorithm;