Enhancement - Command Line Parsing

- Fixed problem where a blank ID was considered valid.  For example,
  the command "task 1 -2" should use -2 as the description, but instead
  considered this to be the sequence 1,0,2.
- Replaced old validId calls with the new validSequence calls.
- A sequence has been redefined to be the first set of consecutive
  arguments that look like sequences.  Once broken by a non-sequence
  argument, all remaining args, even if they look like a sequence,
  are not considered part of the sequence.  This allows commands like
  "task append 1,3-5 Write 10 emails", where 10 is not part of the
  sequence because of the intervening "Write".
- Unit tests (parse.t.cpp) that exercise the parsing of sequences.
  Should probably be expanded to cover more.

src/tests/Makefile

@@ -1,4 +1,5 @@
-PROJECT = t.t tdb.t date.t duration.t t.benchmark.t text.t autocomplete.t
+PROJECT = t.t tdb.t date.t duration.t t.benchmark.t text.t autocomplete.t \
+          parse.t
 CFLAGS  = -I. -I.. -Wall -pedantic -ggdb3 -fno-rtti
 LFLAGS  = -L/usr/local/lib
 OBJECTS = ../TDB.o ../T.o ../parse.o ../text.o ../Date.o ../util.o ../Config.o
@@ -38,3 +39,6 @@ text.t: text.t.o $(OBJECTS) test.o
 autocomplete.t: autocomplete.t.o $(OBJECTS) test.o
 	g++ autocomplete.t.o $(OBJECTS) test.o $(LFLAGS) -o autocomplete.t
 
+parse.t: parse.t.o $(OBJECTS) test.o
+	g++ parse.t.o $(OBJECTS) test.o $(LFLAGS) -o parse.t
+