Block device peripheral and SBFS file system implemented.

Tests/expected/branchTest.out

@@ -0,0 +1,4 @@
+QAB C qab c
+9876543210
+Execution halted after 176 cycles.
+[exit 0]

Tests/expected/diskProtectTest.out

@@ -0,0 +1,5 @@
+04
+04
+06
+Execution halted after 114 cycles.
+[exit 0]

Tests/expected/diskTest.out

@@ -0,0 +1,5 @@
+00
+from the disk
+02
+Execution halted after 245 cycles.
+[exit 0]

Tests/expected/loader.out

@@ -0,0 +1,4 @@
+loader
+loaded off a disk, with a string and a loop of its own
+Execution halted after 1098 cycles.
+[exit 0]

Tests/expected/sbfsReadTest.out

@@ -0,0 +1,7 @@
+greeting.txt 0000 11 hello from a file
+across.txt 0002 BC ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWX
+aName22CharactersLong! 0000 16 exactly twenty two!!!!
+empty.txt 0000 00 
+absent.txt missing
+Execution halted after 19230 cycles.
+[exit 0]

Tests/expected/sbfsWriteTest.out

@@ -0,0 +1,5 @@
+here.txt 0002 already here
+first.txt 0003 written by SplitBit itself
+second.txt 0004 and a second one after it
+Execution halted after 5888 cycles.
+[exit 0]