Bugfix: make sure subtree is rehidden after changing attribute

Altered items:
simple-call-tree-set-attribute
Bugfix: simple-call-tree-compare-items

Also use replace-match instead of replace-regexp in simple-call-tree-mark
to make it much faster.
Finish simple-call-tree-toggle-marks and simple-call-tree-mark-by-name
Remove simple-call-tree-get-marked
Start simple-call-tree-mark-by-source

Altered items:
simple-call-tree-compare-items,
simple-call-tree-mark
simple-call-tree-toggle-marks, simple-call-tree-mark-regexp,
simple-call-tree-mark-by-name, simple-call-tree-mark-by-source,
simple-call-tree-get-marked