EComposerPrivate: Fix caret position in "Start typing at the bottom on replying"
Composer should know if it was started with new message
Fix combinations of "start_bottom" and "top_signature" composer settings
Fix various bugs in plain text citation quoting
EEditorSelection: Fix detection of citation

With this commit the situation when Enter is pressed in citation (to break
citation) is fixed
Bug #708731 - [webkit-composer] Cannot set signature to none on re-edit
Let the citation text have the same color as in preview (light grey)
Move replace_string from Backup-Restore module to e-misc-utils and make it public as e_str_replace_string
Replace some usage of GRegex with e_str_replace_string
EComposerPrivate - Fix compilation warnings
EEditorSelection - Fix detection of Blockquote block format
EEditorSelection - Refactorization
EEditorWidget - Always put text in some paragraph
EEditorSelection - When unindenting force the spell check
EEditorWidget - When changing composer mode, change paragraphs style as well

In plain text mode (Normal paragraph format) we are limiting the width
of the paragraph. In HTML mode we have to remove these limits.
EEditorSelection: Return Node instead of Element in e_editor_selection_get_caret_position_node
EEditorWidget: Remove unneeded Unicode ZERO WIDTH SPACE characters while typing

Also rename UNICODE_HIDDEN_SPACE to UNICODE_ZERO_WIDTH_SPACE
EEditorWidget: Fix smileys handling in composer

For every smiley in HTML mode (typed in text form or inserted from
menu) we create span wrapper that containes image and also text
representation. Afterwards when changing composer mode we are just
showing/hiding the unwanted one (in plain text mode we hide the
image representation and vice versa).
EEditorSelection: Fix indentation and unnecessary empty line
EEditorWidget: Surround with paragraph only if writing straight into BODY